Laser processing system, laser processing method, and method for manufacturing electronic device

Abstract

The laser processing system includes: a laser device that outputs pulsed laser light; a diffractive optical element that divides the pulse laser light into light including first diffracted light that is a plurality of diffracted light that is irradiated to a plurality of processing points of the workpiece, and second diffracted light that is a plurality of diffracted light that is irradiated to a plurality of non-processing points; a condensing optical system that condenses the first diffracted light and the second diffracted light on the workpiece; an adjustment mechanism configured so as to be able to adjust the pulse energy of the pulse laser light incident on the diffractive optical element; and a processor that controls the adjustment mechanism so that the fluence FOKm of the first diffracted light at the surface of the workpiece is greater than the machining threshold Fth and the fluence FNGm of the second diffracted light at the surface of the workpiece is equal to or less than the machining threshold Fth on the basis of a parameter including the machining threshold Fth of the fluence for machining the workpiece.

Description

Technical Field

[0001] The present disclosure relates to a laser processing system, a laser processing method, and a method for manufacturing an electronic device. Background Art

[0002] In recent years, in semiconductor exposure apparatuses, with the miniaturization and high integration of semiconductor integrated circuits, an improvement in resolution has been required. Therefore, the shortening of the wavelength of light emitted from an exposure light source has been developed. For example, as a gas laser device for exposure, a KrF excimer laser device that uses a laser having an output wavelength of approximately 248 nm and an ArF excimer laser device that uses a laser having an output wavelength of approximately 193 nm are used.

[0003] The pulse widths of the excimer lasers respectively output from the KrF and ArF excimer laser devices are several 10 ns, and the wavelengths are short at approximately 248 nm and approximately 193 nm. Therefore, they can be used for direct processing of polymer materials, glass materials, and the like.

[0004] Chemical bonds in polymer materials can be broken by an excimer laser having a photon energy higher than the bond energy. Therefore, it is known that non-thermal processing of polymer materials can be performed by an excimer laser, and the processed shape becomes regular.

[0005] In addition, it is known that glass, ceramics, etc. have a high absorption rate for an excimer laser. Therefore, even materials that are difficult to process with lasers in the visible or infrared regions can be processed with an excimer laser.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: US Patent Application Publication No. 2004 / 0150887

[0009] Patent Document 2: US Patent Application Publication No. 2006 / 0289412 Summary of the Invention

[0010] One aspect of the laser processing system of the present disclosure includes: a laser device that outputs pulsed laser light; a diffractive optical element that splits the pulsed laser light into light including first diffracted light and second diffracted light, where the first diffracted light is a plurality of diffracted lights that are respectively irradiated onto a plurality of processing points of the workpiece, and the second diffracted light is a plurality of diffracted lights that are irradiated onto a plurality of non-processing points; a condensing optical system that converges the first diffracted light and the second diffracted light onto the workpiece respectively; an adjustment mechanism configured to be able to adjust the pulse energy of the pulsed laser light incident on the diffractive optical element; and a processor that controls the adjustment mechanism according to a parameter including a processing threshold Fth for the fluence for processing the workpiece, so that the fluence F OK m of the first diffracted light at the surface of the workpiece is greater than the processing threshold Fth, and the fluence F NG m of the second diffracted light at the surface of the workpiece becomes below the processing threshold Fth.

[0011] One aspect of the laser processing method of the present disclosure includes the following steps: outputting pulsed laser light from a laser device, splitting the pulsed laser light into light including first diffracted light and second diffracted light through a diffractive optical element, where the first diffracted light is a plurality of diffracted lights that are respectively irradiated onto a plurality of processing points of the workpiece, and the second diffracted light is a plurality of diffracted lights that are irradiated onto a plurality of non-processing points, controlling an adjustment mechanism for adjusting the pulse energy of the pulsed laser light according to a parameter including a processing threshold Fth for the fluence for processing the workpiece, so that the fluence F OK m of the first diffracted light at the surface of the workpiece is greater than the processing threshold Fth, and the fluence F NG m of the second diffracted light at the surface of the workpiece becomes below the processing threshold Fth, and converging the first diffracted light and the second diffracted light onto the workpiece respectively through a condensing optical system.

[0012] One aspect of the manufacturing method of an electronic device of the present disclosure includes the following steps: laser processing an interposer substrate through a laser processing system to fabricate an interposer, bonding the interposer and an integrated circuit chip to electrically connect them to each other, bonding the interposer and a circuit substrate to electrically connect them to each other, and the laser processing system includes: a laser device that outputs pulsed laser light; a diffractive optical element that splits the pulsed laser light into light including first diffracted light and second diffracted light, where the first diffracted light is a plurality of diffracted lights that are respectively irradiated onto a plurality of processing points of the workpiece, and the second diffracted light is a plurality of diffracted lights that are irradiated onto a plurality of non-processing points; a condensing optical system that converges the first diffracted light and the second diffracted light onto the workpiece respectively; an adjustment mechanism configured to be able to adjust the pulse energy of the pulsed laser light incident on the diffractive optical element; and a processor that controls the adjustment mechanism according to a parameter including a processing threshold Fth for the fluence for processing the workpiece, so that the fluence F OKm is greater than the processing threshold Fth, and the fluence F of the second diffracted light at the surface of the workpiece NG m becomes equal to or less than the processing threshold Fth. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Hereinafter, several embodiments of the present disclosure will be described by way of example only with reference to the drawings.

[0014] Figure 1 Schematically shows the structure of a laser processing system of a comparative example.

[0015] Figure 2 Is a cross-sectional view of a diffraction grating that is the basis of a diffractive optical element.

[0016] Figure 3 Shows a combination of multiple diffraction gratings for explaining the principle of a diffractive optical element.

[0017] Figure 4 Shows an example of a designed diffractive optical element.

[0018] Figure 5 Shows an example of the pattern of diffracted light irradiated from a diffractive optical element onto a workpiece.

[0019] Figure 6 Is a flowchart showing the process of laser processing in a comparative example.

[0020] Figure 7 Is a flowchart showing the details of the process of reading information of a laser processing system.

[0021] Figure 8 Is a flowchart showing the details of the process of reading information of a workpiece.

[0022] Figure 9 Is a graph showing an example of the definition of a processing threshold.

[0023] Figure 10 Is a flowchart showing the details of the process of reading information of a diffractive optical element.

[0024] Figure 11 Is a flowchart showing the details of the process of determining the target fluence at a processing point.

[0025] Figure 12 Is a flowchart showing the details of the process of determining the number of irradiation pulses and the repetition frequency in one laser processing.

[0026] Figure 13 Is a flowchart showing the details of the process of adjusting a laser processing system according to the target fluence.

[0027] Figure 14It is a flowchart showing the details of the process of performing laser processing.

[0028] Figure 15 It shows another example of the pattern of diffracted light irradiated from the diffractive optical element onto the workpiece.

[0029] Figure 16 It is a bar graph showing the problems of the comparative example.

[0030] Figure 17 It is a bar graph showing an example of the control result in the first embodiment.

[0031] Figure 18 It is a bar graph showing an example of the target fluence of the first diffracted light set in the first embodiment.

[0032] Figure 19 It is a flowchart showing the process of laser processing in the first embodiment.

[0033] Figure 20 It is a flowchart showing the details of the process of reading information of the diffractive optical element.

[0034] Figure 21 It is a flowchart showing the details of the process of determining the target fluence at the processing point.

[0035] Figure 22 It is a flowchart showing the details of the process of determining the number of irradiation pulses and the repetition frequency in one laser processing.

[0036] Figure 23 It is a flowchart showing the details of the process of adjusting the laser processing system according to the target fluence.

[0037] Figure 24 It is a bar graph showing an example of the control result in the second embodiment.

[0038] Figure 25 It is a bar graph showing an example of the target fluence of the first minimum diffracted light set in the second embodiment.

[0039] Figure 26 It schematically shows the structure of the measurement system for measuring information of the diffractive optical element in the second embodiment.

[0040] Figure 27 It is a flowchart showing the process of light intensity measurement in the second embodiment.

[0041] Figure 28 It is a flowchart showing the process of laser processing in the second embodiment.

[0042] Figure 29It is a flowchart showing the details of the process of reading information of the diffractive optical element.

[0043] Figure 30 It is a flowchart showing the details of the process of determining the target fluence of the first minimum diffracted light.

[0044] Figure 31 It is a flowchart showing the details of the process of determining the number of irradiation pulses and the repetition frequency in the single-pulse laser processing.

[0045] Figure 32 It is a flowchart showing the details of the process of adjusting the laser processing system according to the target fluence.

[0046] Figure 33 It is a bar chart showing an example of the control result in the modification of the second embodiment.

[0047] Figure 34 It is a bar chart showing an example of the target fluence of the first minimum diffracted light set in the modification of the second embodiment.

[0048] Figure 35 It is a flowchart showing the process of laser processing in the modification of the second embodiment.

[0049] Figure 36 It is a flowchart showing the details of the process of reading information of the laser processing system.

[0050] Figure 37 It is a flowchart showing the details of the process of determining the target fluence of the first minimum diffracted light.

[0051] Figure 38 It is a bar chart showing an example of the control result in the third embodiment.

[0052] Figure 39 It is a graph showing an example of the definition of the fluence upper limit value.

[0053] Figure 40 It is a bar chart showing an example of the target fluence of the first minimum diffracted light set in the third embodiment.

[0054] Figure 41 It is a bar chart showing an example of the target fluence of the first minimum diffracted light set in the third embodiment.

[0055] Figure 42 It is a flowchart showing the process of light intensity measurement in the third embodiment.

[0056] Figure 43 It is a flowchart showing the process of laser processing in the third embodiment.

[0057] Figure 44 It is a flowchart showing details of the process of reading information of the workpiece to be processed.

[0058] Figure 45 It is a flowchart showing details of the process of reading information of the diffractive optical element.

[0059] Figure 46 It is a flowchart showing details of the process of determining the target fluence of the first minimum diffracted light.

[0060] Figure 47 It is a bar graph showing an example of the control result in the modification of the third embodiment.

[0061] Figure 48 It is a bar graph showing an example of the target fluence of the first minimum diffracted light set in the modification of the third embodiment.

[0062] Figure 49 It is a flowchart showing the process of laser processing in the modification of the third embodiment.

[0063] Figure 50 It is a flowchart showing details of the process of determining the target fluence of the first minimum diffracted light.

[0064] Figure 51 Schematically shows the structure of the electronic device.

[0065] Figure 52 It is a flowchart showing the manufacturing method of the electronic device. Detailed implementation mode

[0066] <Content>

[0067] 1. Laser processing system of the comparative example

[0068] 1.1 Structure

[0069] 1.1.1 Structure of the laser device 1

[0070] 1.1.2 Structure of the laser processing device 5

[0071] 1.1.3 Structure of the data management server 93

[0072] 1.2 Operation

[0073] 1.2.1 Operation of the laser device 1

[0074] 1.2.2 Operation of the laser processing device 5

[0075] 1.3 Diffractive optical element 63

[0076] 1.4 Processing of the laser processing processor 53

[0077] 1.4.1 Reading of Laser Processing System Information

[0078] 1.4.2 Reading of Workpiece Information

[0079] 1.4.3 Reading of Diffractive Optical Element Information

[0080] 1.4.4 Determination of Target Fluence

[0081] 1.4.5 Determination of Number of Irradiation Pulses Nm and Repetition Frequency f

[0082] 1.4.6 Adjustment of Laser Processing System

[0083] 1.4.7 Laser Processing

[0084] 1.5 Problems of Comparative Examples

[0085] 2. Laser Processing System for Setting Target Fluence So That Fluence of Second Diffracted Light Is Below Processing Threshold Fth

[0086] 2.1 Concept

[0087] 2.1.1 Fluence of First Diffracted Light and Second Diffracted Light

[0088] 2.1.2 Target Fluence F OK Setting of mt

[0089] 2.1.2.1 Target Fluence F OK Lower Limit of mt

[0090] 2.1.2.2 Target Fluence F OK Upper Limit of mt

[0091] 2.1.2.3 Target Fluence F OK Range of mt

[0092] 2.2 Structure of Laser Processing System

[0093] 2.3 Processing of Laser Processing Processor 53

[0094] 2.3.1 Reading of Diffractive Optical Element Information

[0095] 2.3.2 Determination of Target Fluence

[0096] 2.3.3 Determination of Number of Irradiation Pulses Nm and Repetition Frequency f

[0097] 2.3.4 Adjustment of Laser Processing System

[0098] 2.4 Function

[0099] 3. Laser processing system that takes into account the deviation of fluence between the first diffracted light and the second diffracted light

[0100] 3.1 Concept

[0101] 3.1.1 Fluence of the first diffracted light and the second diffracted light

[0102] 3.1.2 Target fluence F OK Setting of mint

[0103] 3.1.2.1 Target fluence F OK Lower limit of mint

[0104] 3.1.2.2 Target fluence F OK Upper limit of mint

[0105] 3.1.2.3 Target fluence F OK Range of mint

[0106] 3.2 Structure of the laser processing system

[0107] 3.3 Measurement of diffractive optical element information

[0108] 3.4 Processing of the laser processing processor 53

[0109] 3.4.1 Reading in of diffractive optical element information

[0110] 3.4.2 Determination of the target fluence

[0111] 3.4.3 Determination of the irradiation pulse number Nm and the repetition frequency f

[0112] 3.4.4 Adjustment of the laser processing system

[0113] 3.5 Function

[0114] 4. Laser processing system that takes into account the pulse energy deviation of the pulsed laser output from the laser device

[0115] 4.1 Concept

[0116] 4.1.1 Fluence of the first diffracted light and the second diffracted light

[0117] 4.1.2 Target fluence F OK Setting of mint

[0118] 4.1.2.1 Target fluence F OK Lower limit of mint

[0119] 4.1.2.2 Target fluence F OK Upper limit of mint

[0120] 4.1.2.3 Target fluence FOK Range of mint

[0121] 4.2 Structure of the laser processing system

[0122] 4.3 Processing of the laser processing processor 53

[0123] 4.3.1 Reading of laser processing system information

[0124] 4.3.2 Determination of the target fluence

[0125] 4.4 Function

[0126] 5. Laser processing system considering the upper limit value of fluence

[0127] 5.1 Concept

[0128] 5.1.1 Fluence of the first diffracted light and the second diffracted light

[0129] 5.1.2 Target fluence F OK Setting of mint

[0130] 5.1.2.1 Target fluence F OK Lower limit of mint

[0131] 5.1.2.2 Target fluence F OK Upper limit of mint (1)

[0132] 5.1.2.3 Target fluence F OK Upper limit of mint (2)

[0133] 5.1.2.4 Target fluence F OK Range of mint

[0134] 5.2 Structure of the laser processing system

[0135] 5.3 Measurement of diffractive optical element information

[0136] 5.4 Processing of the laser processing processor 53

[0137] 5.4.1 Reading of workpiece information

[0138] 5.4.2 Reading of diffractive optical element information

[0139] 5.4.3 Determination of the target fluence

[0140] 5.5 Function

[0141] 6. Laser processing system considering the upper limit value of fluence and the pulse energy deviation of the pulsed laser output from the laser device

[0142] 6.1 Concept

[0143] 6.1.1 Fluence of the First Diffracted Light and the Second Diffracted Light

[0144] 6.1.2 Target Fluence F OK Setting of mint

[0145] 6.1.2.1 Target Fluence F OK Lower Limit of mint

[0146] 6.1.2.2 Target Fluence F OK Upper Limit (1) of mint

[0147] 6.1.2.3 Target Fluence F OK Upper Limit (2) of mint

[0148] 6.1.2.4 Target Fluence F OK Range of mint

[0149] 6.2 Structure of the Laser Processing System

[0150] 6.3 Processing of the Laser Processing Processor 53

[0151] 6.4 Function

[0152] 7. Others

[0153] 7.1 Structure of the Electronic Device

[0154] 7.2 Manufacturing Method of the Electronic Device

[0155] 7.3 Supplement

[0156] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The embodiments described below show several examples of the present disclosure and do not limit the content of the present disclosure. In addition, the structures and operations described in each embodiment are not necessarily all essential to the structures and operations of the present disclosure. In addition, the same reference numerals are assigned to the same structural elements and repeated descriptions are omitted.

[0157] 1. Laser Processing System of the Comparative Example

[0158] 1.1 Structure

[0159] Figure 1 The structure of the laser processing system of the comparative example is schematically shown. The comparative example of the present disclosure is a way known only to the applicant and is not a publicly known example admitted by the applicant. The laser processing system includes a laser device 1, a laser processing device 5, and a data management server 93.

[0160] 1.1.1 Structure of the Laser Device 1

[0161] The laser device 1 is a gas laser device that outputs pulsed laser Out of ultraviolet light. The laser device 1 includes a laser cavity 10, a power supply device 12, a rear mirror 14, an output coupling mirror 15, a monitor module 16, and a shutter 19. These structural elements are housed in the first housing 100. The rear mirror 14 and the output coupling mirror 15 constitute an optical resonator.

[0162] The laser cavity 10 is disposed on the optical path of the optical resonator. Windows 10a and 10b are provided in the laser cavity 10. The laser cavity 10 has a pair of discharge electrodes 11a and 11b inside. For example, a laser gas is enclosed in the laser cavity 10, and the laser gas includes argon or krypton as a noble gas, fluorine as a halogen gas, neon as a buffer gas, and the like.

[0163] The rear mirror 14 is composed of a highly reflective mirror, and the output coupling mirror 15 is composed of a partial reflection mirror. The pulsed laser Out is output from the output coupling mirror 15.

[0164] The monitor module 16 includes a beam splitter 17 and a light sensor 18. The beam splitter 17 is located on the optical path of the pulsed laser Out output from the output coupling mirror 15. The light sensor 18 is located on the optical path of the pulsed laser Out reflected by the beam splitter 17.

[0165] The shutter 19 is located on the optical path of the pulsed laser Out that has passed through the beam splitter 17. The shutter 19 is configured to be able to switch the passage and blocking of the pulsed laser Out incident on the laser processing device 5.

[0166] The laser device 1 further includes a laser control processor 13. The laser control processor 13 is a processing device that includes a memory 13a storing a control program and a CPU (central processing unit) 13b that executes the control program. The laser control processor 13 is specifically configured or programmed to execute various processes included in the present disclosure.

[0167] 1.1.2 Structure of the laser processing device 5

[0168] The laser processing device 5 includes an irradiation optical system 50a, a frame 50b, an XYZ stage 501, and a laser processing processor 53. The irradiation optical system 50a and the XYZ stage 501 are fixed to the frame 50b. A workpiece SUB is supported on the stage 502 of the XYZ stage 501.

[0169] In Figure 1 the X direction and the Y direction that are orthogonal to each other are directions parallel to the surface of the workpiece SUB. The Z direction is a direction perpendicular to the surface of the workpiece SUB and parallel to the traveling direction of the pulsed laser Out incident on the surface of the workpiece SUB.

[0170] The workpiece SUB is, for example, an interposer substrate for manufacturing an interposer IP that relays an integrated circuit chip IC and a circuit substrate CS described later. The interposer substrate is made of, for example, an electrically insulating material such as a polymer material, a glass material, single crystal silicon, or ceramics. The workpiece SUB is not limited to the interposer substrate and may also be a substrate having a metal film to be laser processed formed on its surface. Figure 51 The irradiation optical system 50a includes high reflectors 51a, 51b, and 51c, an attenuator 52, a diffractive optical element 63, and a condensing optical system 67. The high reflectors 51a, 51b, and 51c, the attenuator 52, and the diffractive optical element 63 are housed in the second housing 500. The condensing optical system 67 also serves as a window of the second housing 500. The second housing 500 is connected to the first housing 100 via an optical path tube 200. The pulsed laser Out output from the laser device 1 enters the second housing 500 through the inside of the optical path tube 200.

[0171] The high reflector 51a is located on the optical path of the pulsed laser Out after passing through the inside of the optical path tube 200. The attenuator 52 is located on the optical path of the pulsed laser Out reflected by the high reflector 51a. The attenuator 52 includes two partial reflectors 52a and 52b and rotating stages 52c and 52d. The rotating stages 52c and 52d are configured to change the incident angles of the pulsed laser Out with respect to the partial reflectors 52a and 52b, respectively, thereby enabling the transmittance Ta of the attenuator 52 to be changed.

[0172] The high reflector 51b is located on the optical path of the pulsed laser Out that has passed through the attenuator 52, and the high reflector 51c is located on the optical path of the pulsed laser Out reflected by the high reflector 51b.

[0173] The diffractive optical element 63 is located on the optical path of the pulsed laser Out reflected by the high reflector 51c. The diffractive optical element 63 is configured to have a large number of irregularities on its surface and diffract the pulsed laser Out to be transmitted, thereby splitting it into multiple diffracted lights.

[0174] The condensing optical system 67 is located on the optical path of the pulsed laser Out that has passed through the diffractive optical element 63. The condensing optical system 67 converges the diffracted lights of the pulsed laser Out split by the diffractive optical element 63 onto the workpiece SUB, respectively. The condensing optical system 67 has a focal length f

[0175] . Preferably, the condensing optical system 67 is composed of an Fθ lens so that the diffracted lights of the pulsed laser Out are converged on the same plane. 67

[0176] The laser processing processor 53 is a processing device including a memory 53a storing a control program and a CPU 53b executing the control program. The laser processing processor 53 corresponds to the processor in the present disclosure. The laser processing processor 53 is specifically configured or programmed to execute various processes included in the present disclosure.

[0177] 1.1.3 Structure of the data management server 93

[0178] The data management server 93 is a data server that manages laser processing system information, workpiece information, and diffractive optical element information. The laser processing processor 53 can access the data management server 93 to read in information.

[0179] 1.2 Operations

[0180] 1.2.1 Operations of the laser device 1

[0181] In the laser device 1, the laser control processor 13 receives the data of the target pulse energy Et and the trigger signal from the laser processing processor 53. The laser control processor 13 sets the voltage of the power supply device 12 according to the target pulse energy Et and transmits the trigger signal to the power supply device 12.

[0182] When the power supply device 12 receives the trigger signal from the laser control processor 13, it generates a pulsed high voltage and applies it between the discharge electrodes 11a and 11b.

[0183] When a high voltage is applied between the discharge electrodes 11a and 11b, a discharge occurs between the discharge electrodes 11a and 11b. By the energy of this discharge, the laser gas in the laser cavity 10 is excited and transitions to a high energy level. Then, when the excited laser gas transitions to a low energy level, light of a wavelength corresponding to the energy level difference is emitted.

[0184] The light generated in the laser cavity 10 exits the laser cavity 10 through the windows 10a and 10b. The light exiting from the window 10a of the laser cavity 10 is reflected by the rear mirror 14 with a high reflectivity and returns to the laser cavity 10.

[0185] The output coupling mirror 15 allows a part of the light exiting from the window 10b of the laser cavity 10 to pass through and be output, and reflects another part back to the laser cavity 10.

[0186] In this way, the light exiting from the laser cavity 10 reciprocates between the rear mirror 14 and the output coupling mirror 15 and is amplified each time it passes through the discharge space between the discharge electrodes 11a and 11b. The pulsed laser Out generated by such laser oscillation is output from the output coupling mirror 15.

[0187] The monitor module 16 detects the pulse energy of the pulsed laser Out output from the output coupling mirror 15. The monitor module 16 sends the data of the detected pulse energy to the laser control processor 13.

[0188] Based on the data of the pulse energy received from the monitor module 16 and the data of the target pulse energy Et received from the laser processing processor 53, the laser control processor 13 performs feedback control on the set voltage of the power supply device 12.

[0189] 1.2.2 Operation of the laser processing device 5

[0190] The XYZ stage 501 is adjusted so that the workpiece SUB is located at a position that is the focal length f from the condenser optical system 67. 67 away.

[0191] The pulsed laser Out output from the laser device 1 enters the laser processing device 5 through the inside of the optical path tube 200. The pulsed laser Out is reflected by the high reflector 51a, passes through the attenuator 52, and is then reflected successively by the high reflectors 51b and 51c. The laser processing processor 53 sets the target value of the transmittance Ta of the attenuator 52 and controls the turntables 52c and 52d based on this target value.

[0192] The pulsed laser Out reflected by the high reflector 51c is split into a plurality of diffracted lights by the diffractive optical element 63, and the diffracted lights are respectively converged by the condenser optical system 67 onto the surface of the workpiece SUB. When the diffracted lights of the pulsed laser Out are irradiated onto the workpiece SUB, the surface of the workpiece SUB is ablated by laser processing.

[0193] 1.3 Diffractive optical element 63

[0194] Figure 2 is a cross-sectional view of the diffraction grating 631 that forms the basis of the diffractive optical element 63. The diffraction grating 631 is made of a material that allows the pulsed laser Out with a wavelength λ to pass through, and is a plate having a large number of grooves with a grating period p formed on its surface. The pulsed laser Out passing through the diffraction grating 631 is split into a plurality of diffracted lights including the 0th-order diffracted light, the -1st-order diffracted light, the +1st-order diffracted light, and higher-order diffracted lights (not shown). In Figure 2 where m represents the order of the diffracted light. When θ is very small, the angle θ formed by the emission directions of the -1st-order diffracted light and the +1st-order diffracted light with respect to the emission direction of the 0th-order diffracted light is approximately given by λ / p. The energy of each diffracted light can also be obtained by calculation. Generally, higher-order diffracted lights than the -1st-order diffracted light and the +1st-order diffracted light become diffracted lights with an energy smaller than that of the -1st-order diffracted light and the +1st-order diffracted light.

[0195] Figure 3Shows a combination of a plurality of diffraction gratings 631 to 635 for explaining the principle of the diffractive optical element 63. When the diffraction gratings 631 to 635 having different grating periods from each other are appropriately combined, the diffractive optical element 63 can be designed in such a way that a plurality of diffracted lights become a desired pattern. Figure 4 Shows an example of the designed diffractive optical element 63.

[0196] Figure 5 Shows an example of the pattern of the diffracted light irradiated from the diffractive optical element 63 to the workpiece SUB. For example, the diffractive optical element 63 is designed to emit 16 diffracted lights having desired emission directions respectively. Each diffracted light is converged by the condenser optical system 67 to a desired processing point on the workpiece SUB. Thereby, 16 fine holes are simultaneously machined in the workpiece SUB. When the position of the XYZ stage 501 is fixed, a pulsed laser with the irradiation pulse number Nm is irradiated, whereby 16 holes with the required depth are formed in one processing area. The irradiation pulse number Nm is obtained by dividing the required depth of the hole by the depth of the hole formed by one pulse of the pulsed laser Out. Sometimes the process of irradiating the pulsed laser with the irradiation pulse number Nm is called one-time laser processing. Sometimes the convergence point of each diffracted light forming the hole is called the processing point. After one-time laser processing, in order to form 16 holes in other processing areas of the workpiece SUB, the position of the XYZ stage 501 is controlled.

[0197] It is also considered to perform mask-based pattern processing by irradiating the workpiece SUB with a pulsed laser that has passed through a mask and a transfer optical system (not shown), but a large amount of energy loss occurs in the mask. In contrast, by forming a pattern of diffracted light with the diffractive optical element 63, energy loss can be reduced and the processing speed can be increased.

[0198] 1.4 Processing of the laser processing processor 53

[0199] Figure 6 Is a flowchart showing the processing of laser processing in the comparative example. In S100, the laser processing processor 53 reads in the information of the laser processing system. In S200, the laser processing processor 53 reads in the information of the workpiece SUB. In S300, the laser processing processor 53 reads in the information of the diffractive optical element 63. The information read in S100 to S300 can be read in from the data management server 93 or from the internal memory 53a of the laser processing processor 53.

[0200] In S400, the laser processing processor 53 determines the target fluence Fmt at the processing point. In S500, the laser processing processor 53 determines the number of irradiation pulses Nm and the repetition frequency f in one laser processing. In S600, the laser processing processor 53 adjusts the laser processing system according to the target fluence Fmt. In S700, the laser processing processor 53 controls the laser processing system to perform laser processing. The following refers to Figures 7 - 14 The details of each process will be described.

[0201] 1.4.1 Reading of Laser Processing System Information

[0202] Figure 7 It is a flowchart showing the details of the process of reading the information of the laser processing system. Figure 7 The process shown corresponds to Figure 6 The subroutine of S100 of

[0203] In S101, the laser processing processor 53 reads the transmittance T0 of the optical path of the pulsed laser Out other than the diffractive optical element 63 and the attenuator 52. Assuming that the transmittance T DOE of the diffractive optical element 63 and the transmittance Ta of the attenuator 52 are 100%, the transmittance T0 corresponds to the proportion of the energy of the light incident on the workpiece SUB in the energy of the pulsed laser Out output from the output coupling mirror 15.

[0204] In S102, the laser processing processor 53 reads the number of holes P to be processed simultaneously. The number of holes P corresponds to the number of processing points, and in Figure 5 the example shown is 16.

[0205] In S103, the laser processing processor 53 reads the irradiation area S of the diffracted light for processing one hole on the surface of the workpiece SUB. When the beam cross-section of one diffracted light on the surface of the workpiece SUB is a circle with a diameter D, the irradiation area S is given by π(D / 2) 2 ^2.

[0206] After S103, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 6 the process shown.

[0207] 1.4.2 Reading of Workpiece Information

[0208] Figure 8 It is a flowchart showing the details of the process of reading the information of the workpiece SUB. Figure 8 The process shown corresponds to Figure 6 the subroutine of S200 of

[0209] In S201, the laser processing processor 53 reads in the processing threshold Fth of the workpiece SUB. The processing threshold Fth is the threshold of the fluence of the diffracted light used to process the workpiece SUB. Even if the pulsed laser is irradiated with a fluence below the processing threshold Fth, the workpiece SUB will not be processed. When the pulsed laser is irradiated with a fluence exceeding the processing threshold Fth, the workpiece SUB is processed. The processing threshold Fth is referred to Figure 9 and will be described later.

[0210] In S202, the laser processing processor 53 reads in the thickness t of the workpiece SUB. When forming a through hole in the workpiece SUB, it is sufficient that the value obtained by multiplying the depth of the hole formed by one pulse of the pulsed laser by the number of irradiation pulses Nm is equal to or greater than the thickness t.

[0211] After S202, the laser processing processor 53 ends the processing of this flowchart and returns Figure 6 to the processing shown.

[0212] Figure 9 is a graph showing an example of the definition of the processing threshold Fth. Figure 9 The horizontal axis of is the fluence of the diffracted light, and the vertical axis is the processing speed. The processing speed is the depth of the hole per one pulse of the pulsed laser. When the fluence and the processing speed are plotted based on the measurement results, the horizontal axis value of the point where the approximate straight line intersects the horizontal axis indicating that the processing speed becomes 0 is the processing threshold Fth.

[0213] 1.4.3 Reading of Diffractive Optical Element Information

[0214] Figure 10 is a flowchart showing the details of the process of reading the information of the diffractive optical element 63. Figure 10 The processing shown corresponds to Figure 6 the subroutine of S300.

[0215] In S301, the laser processing processor 53 reads in the transmittance T of the diffractive optical element 63 DOE .

[0216] The information of the diffractive optical element 63 may also include the number Ln of diffracted lights. The process of reading the information of the diffractive optical element 63 may also include the step of reading the number Ln of diffracted lights and then confirming that the number Ln of diffracted lights is consistent with the number P of holes to be processed simultaneously (refer to Figure 7 ).

[0217] After S301, the laser processing processor 53 ends the processing of this flowchart and returns Figure 6 to the processing shown.

[0218] 1.4.4 Determination of Target Fluence

[0219] Figure 11 It is a flowchart showing details of the process for determining the target fluence Fmt at the machining point. Figure 11 The process shown is equivalent to Figure 6 a subroutine of S400 of

[0220] In S410, the laser machining processor 53 determines the target fluence Fmt that satisfies the following equation.

[0221] Fth < Fmt

[0222] When the pulsed laser is irradiated with a fluence exceeding the machining threshold Fth, the workpiece SUB is machined.

[0223] After S410, the laser machining processor 53 ends the process of this flowchart and returns to Figure 6 the process shown.

[0224] 1.4.5 Determination of the number of irradiation pulses Nm and the repetition frequency f

[0225] Figure 12 It is a flowchart showing details of the process for determining the number of irradiation pulses Nm and the repetition frequency f in one laser machining. Figure 12 The process shown is equivalent to Figure 6 a subroutine of S500 of

[0226] In S501, the laser machining processor 53 determines the number of irradiation pulses Nm based on the target fluence Fmt and the thickness t.

[0227] In S502, the laser machining processor 53 determines the repetition frequency f suitable for machining. The repetition frequency f is set within the rated repetition frequency range of the laser device 1. However, when the repetition frequency f is too high, the shape of the holes formed in the workpiece SUB may deviate, and it is preferably set within a range that suppresses such deviation.

[0228] After S502, the laser machining processor 53 ends the process of this flowchart and returns to Figure 6 the process shown.

[0229] 1.4.6 Adjustment of the laser machining system

[0230] Figure 13 It is a flowchart showing details of the process for adjusting the laser machining system according to the target fluence Fmt. Figure 13 The process shown is equivalent to Figure 6 a subroutine of S600 of

[0231] In S601, the laser processing processor 53 sets the target pulse energy Et of the laser device 1 and sends it to the laser device 1. The target pulse energy Et is the pulse energy within the range that can maintain the performance of the laser device 1.

[0232] The laser control processor 13 of the laser device 1 that has received the target pulse energy Et closes the shutter 19 and controls the laser device 1 to perform adjustment oscillation based on the target pulse energy Et. After the value of the pulse energy of the pulsed laser Out measured by the monitor module 16 stabilizes within the allowable range near the target pulse energy Et, the laser control processor 13 outputs a pulse energy OK signal.

[0233] In S602, the laser processing processor 53 determines whether a pulse energy OK signal is received from the laser device 1. If the pulse energy OK signal is not received (S602: No), the laser processing processor 53 stands by until the pulse energy OK signal is received. If the pulse energy OK signal is received (S602: Yes), the laser processing processor 53 advances the process to S603.

[0234] In S603, the laser processing processor 53 sets the transmittance Ta of the attenuator 52 as follows.

[0235] The pulse energy of the light incident on the workpiece SUB through the condenser optical system 67 is represented by the following equation.

[0236] Et·Ta·T0·T DOE =Fmt·P·S

[0237] Based on this formula, the transmittance Ta of the attenuator 52 is calculated as follows.

[0238] Ta=Fmt·P·S / (Et·T0·T DOE )

[0239] In S604, the laser processing processor 53 adjusts the attenuator 52 according to the transmittance Ta. Thereby, the pulse energy of the pulsed laser Out incident on the diffractive optical element 63 can be adjusted so that the fluence at the processing point becomes a value near the target fluence Fmt.

[0240] However, the adjustment mechanism for adjusting the pulse energy of the pulsed laser Out incident on the diffractive optical element 63 is not limited to the attenuator 52. By adjusting the target pulse energy Et of the pulsed laser Out output from the output coupling mirror 15, the pulse energy of the pulsed laser Out incident on the diffractive optical element 63 can also be controlled. In this case, the adjustment mechanism is the power supply device 12.

[0241] After S604, the laser processing processor 53 ends the processing of this flowchart and returns Figure 6 to the processing shown

[0242] 1.4.7 Laser processing

[0243] Figure 14 is a flowchart showing the details of the processing for performing laser processing Figure 14 The processing shown corresponds to Figure 6 a subroutine of S700 in

[0244] In S701, the laser processing processor 53 sets the position data of the XYZ stage 501 so that the diffracted light irradiates the initial processing area of the workpiece SUB

[0245] In S702, the laser processing processor 53 positions the XYZ stage 501 in the XY direction according to the set position data

[0246] In S703, the laser processing processor 53 positions the XYZ stage 501 in the Z direction according to the set position data

[0247] In S704, the laser processing processor 53 sends a trigger signal of the repetition frequency f and the number of irradiation pulses Nm to the laser device 1. Thus, one laser processing is performed

[0248] In S705, the laser processing processor 53 determines whether the processing of the workpiece SUB has ended. If there remains an unprocessed processing area (S705: No), the laser processing processor 53 advances the processing to S706. If the processing of all the processing areas has ended (S705: Yes), the laser processing processor 53 ends the processing of this flowchart and returns Figure 6 to the processing shown

[0249] In S706, the laser processing processor 53 sets the position data of the XYZ stage 501 so that the diffracted light irradiates the next processing area. After S706, the laser processing processor 53 returns the processing to S702

[0250] 1.5 Problems of the comparative example

[0251] Figure 15Another example of the pattern of diffraction light irradiated from the diffraction optical element 63 to the workpiece SUB is shown. The diffraction light emitted from the diffraction optical element 63 is not necessarily only the diffraction light required for laser processing. That is, the multiple diffraction lights divided by the diffraction optical element 63 and irradiated to the workpiece SUB include not only the diffraction light converged on the desired processing point of the workpiece SUB, but sometimes also include the diffraction light converged on the non-processing point that is not desired to be processed. The diffraction light that converges on the processing point of the workpiece SUB will be referred to as the first diffraction light, and the diffraction light that converges on the non-processing point of the workpiece SUB will be referred to as the second diffraction light. The first diffraction light is the diffraction light required for laser processing, and the second diffraction light is the diffraction light that is not required in laser processing. In addition, not all the diffraction light that is not required in laser processing is necessarily irradiated to the workpiece SUB. For example, high-order diffracted light among the light diffracted by the diffractive optical element 63 is emitted toward the outside of the condensing optical system 67 or is incident on a wall around a separately provided aperture (not shown), and may not be irradiated to the workpiece SUB.

[0252] Figure 16 : is a bar graph showing the subject of the comparative example. The horizontal axis is configured with the first diffracted light and the second diffracted light, and the vertical axis shows the fluence F of each diffracted light at the surface of the workpiece SUB. When the pulse energy of the pulsed laser Out incident on the diffractive optical element 63 is increased, the fluence of the first diffracted light becomes larger, and it is believed that the efficiency of laser processing can be improved. However, when the pulse energy of the pulsed laser Out is increased, the fluence of the second diffracted light also increases in conjunction. When the fluence of the second diffracted light exceeds the processing threshold Fth, a hole is sometimes formed at a non-processing point of the workpiece SUB.

[0253] 2. Laser processing system that sets the target fluence so that the fluence of the second diffracted light is below the processing threshold Fth

[0254] 2.1 Conception

[0255] 2.1.1 Fluence of the first and second diffracted light

[0256] Figure 17 1 is a bar graph showing an example of the control result in the first embodiment. The horizontal axis is configured with the first diffracted light and the second diffracted light, and the vertical axis shows the fluence F of each diffracted light at the surface of the workpiece SUB. In the first embodiment, the laser processing processor 53 controls the adjustment mechanism such as the attenuator 52 so that the fluence F of the first diffracted light is OK m is larger than the processing threshold Fth, and the second diffracted light flux F NG m becomes equal to or less than the processing threshold value Fth.

[0257] 2.1.2 Target Fluence F OK mt settings

[0258] In the first embodiment, the target fluence F of the first diffracted light is set as follows. OK mt. When controlling the fluence F of the first diffracted light OK m to the target fluence F OK mt, the fluence F of the second diffracted light NG m becomes a value determined according to the light intensity ratio R with respect to the first diffracted light.

[0259] Figure 18 is a bar graph showing an example of the target fluence F of the first diffracted light set in the first embodiment. OK mt. The first diffracted light and the second diffracted light are arranged on the horizontal axis, and the vertical axis shows the fluence F of each diffracted light at the surface of the workpiece SUB. In Figure 18 and those described later Figure 25 , Figure 34 , Figure 40 , Figure 41 and Figure 48 , the vertical arrows show the value ranges. The black arrow means that the value shown at the end of the arrow is included in the range, and the hollow arrow means that the value shown at the end of the arrow is not included in the range.

[0260] 2.1.2.1 Lower limit of the target fluence F OK mt

[0261] The target fluence F OK mt is set to a value larger than the processing threshold Fth. As a result, the fluence F of the first diffracted light OK m becomes a value larger than the processing threshold Fth.

[0262] 2.1.2.2 Upper limit of the target fluence F OK mt

[0263] As shown in the following formula, the value obtained by dividing the light intensity I of the second diffracted light at the surface of the workpiece SUB NG by the light intensity I of the first diffracted light at the surface of the workpiece SUB OK is set as the light intensity ratio R.

[0264] R = I NG / I OK

[0265] The light intensity I of the first diffracted light OK and the light intensity I of the second diffracted light NG are measured, for example, using the measurement system described with reference to Figure 26 . Alternatively, it can also be obtained by simulating the diffracted light based on the design data of the diffractive optical element 63. Regarding the light intensity I of the first diffracted light OKIn the case of deviation, its average value is used for the calculation of the light intensity ratio R. For the light intensity I of the second diffracted light NG In the case of deviation, its average value is used for the calculation of the light intensity ratio R.

[0266] Target fluence F OK mt is set to a value equal to or less than the value Fth / R obtained by dividing the processing threshold Fth by the light intensity ratio R. By setting the target fluence F OK mt to a value equal to or less than the value Fth / R, the fluence F of the second diffracted light NG m becomes a value equal to or less than the processing threshold Fth. Additionally, when setting the target fluence F OK mt to a value greater than the processing threshold Fth, the fluence F of the second diffracted light NG m becomes a value greater than the ratio Fth·R.

[0267] 2.1.2.3 Target fluence F OK Range of mt

[0268] According to Figure 18 and its description, if the target fluence F OK mt is set to the following range, then the fluence F of the first diffracted light OK m becomes a value greater than the processing threshold Fth, and the fluence F of the second diffracted light NG m becomes a value equal to or less than the processing threshold Fth.

[0269] Fth < F OK mt ≤ Fth / R

[0270] 2.2 Structure of the laser processing system

[0271] The structure of the laser processing system according to the first embodiment is the same as the structure of the comparative example described with reference to Figure 1 the description.

[0272] 2.3 Processing of the laser processing processor 53

[0273] Figure 19 is a flowchart showing the processing of laser processing in the first embodiment. Regarding the processing of laser processing in the first embodiment, the processing of S300a, S400a, S500a, and S600a is different from the corresponding processing in the comparative example. The following refers to Figures 20 - 23 for a detailed description of each process.

[0274] 2.3.1 Reading of diffractive optical element information

[0275] Figure 20 is a flowchart showing the details of the process of reading the information of the diffractive optical element 63. Figure 20 The process shown corresponds toFigure 19 Subroutine of S300a

[0276] In S301, the laser processing processor 53 reads in the transmittance T of the diffractive optical element 63 DOE . This is the same as the comparative example

[0277] In S302a, the laser processing processor 53 reads in the value of the light intensity ratio R. The light intensity ratio R is used for reference in Figure 21 the S401a described

[0278] After S302a, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 19 the processing shown

[0279] 2.3.2 Determination of the target fluence

[0280] Figure 21 is a flowchart showing the details of the processing for determining the target fluence F OK mt at the processing point Figure 21 The processing shown is equivalent to Figure 19 the subroutine of S400a

[0281] In S401a, the laser processing processor 53 calculates the fluence F of the second diffracted light by the following formula NG The fluence F of the first diffracted light when m reaches the processing threshold Fth OK mth

[0282] F OK mth = Fth / R

[0283] In S410a, the laser processing processor 53 determines the target fluence F that satisfies the following formula OK mt

[0284] Fth < F OK mt ≤ Fth / R

[0285] The target fluence F OK mt can also be set to Fth / R as the upper limit value. Thus, it is possible to suppress processing of non-processing points that do not require processing and maximize the efficiency of laser processing. Or, the target fluence F OK mt can also be set to the average value of Fth and Fth / R. Thus, even in the case where there is an unexpected deviation in the pulse energy of the pulsed laser Out, it is possible to avoid processing non-processing points and insufficiently processing processing points that require processing

[0286] After S410a, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 19 the processing shown

[0287] 2.3.3 Determination of the number of irradiation pulses Nm and the repetition frequency f

[0288] Figure 22 is a flowchart showing the details of the process for determining the number of irradiation pulses Nm and the repetition frequency f in one laser processing. Figure 22 The process shown corresponds to Figure 19 the subroutine of S500a of

[0289] In S501a, the laser processing processor 53 determines the number of irradiation pulses Nm based on the target fluence F OK mt and the thickness t.

[0290] In S502, the laser processing processor 53 determines the repetition frequency f suitable for processing. This is the same as in the comparative example.

[0291] After S502, the laser processing processor 53 ends the process of this flowchart and returns to Figure 19 the process shown.

[0292] 2.3.4 Adjustment of the laser processing system

[0293] Figure 23 is a flowchart showing the details of the process for adjusting the laser processing system according to the target fluence F OK mt. Figure 23 The process shown corresponds to Figure 19 the subroutine of S600a of

[0294] Regarding Figure 23 the process shown, the calculation formula for setting the transmittance Ta of the attenuator 52 in S603a is different from that of Figure 13 the comparative example shown. The transmittance Ta of the attenuator 52 is calculated by the following formula, using the target fluence F OK mt instead of the target fluence Fmt.

[0295] Ta = F OK mt·P·S / (Et·T0·T DOE )

[0296] In the first embodiment, when calculating the transmittance Ta of the attenuator 52, it is assumed that the total pulse energy of the light that becomes the second diffracted light in the pulsed laser Out incident on the diffractive optical element 63 is much smaller than the pulse energy of the pulsed laser Out.

[0297] Regarding other aspects,[[]] Figure 23 the process shown is the same as Figure 13 the process shown.

[0298] 2.4 Function

[0299] (1) According to the first embodiment, the laser processing system includes a laser device 1, a diffractive optical element 63, a condenser optical system 67, an attenuator 52 and other adjustment mechanisms, and a laser processing processor 53. The laser device 1 outputs pulsed laser Out. The diffractive optical element 63 divides the pulsed laser Out into light including first diffracted light and second diffracted light. The first diffracted light is a plurality of diffracted lights that are respectively irradiated onto a plurality of processing points of the workpiece SUB, and the second diffracted light is a plurality of diffracted lights that are irradiated onto a plurality of non-processing points. The condenser optical system 67 converges the first diffracted light and the second diffracted light onto the workpiece SUB respectively. The adjustment mechanism is configured to be able to adjust the pulse energy of the pulsed laser Out incident on the diffractive optical element 63. The laser processing processor 53 controls the adjustment mechanism according to a parameter including a processing threshold Fth of fluence for processing the workpiece SUB to satisfy the following conditions. (a) The fluence F OK m of the first diffracted light at the surface of the workpiece SUB is larger than the processing threshold Fth. (b) The fluence F NG m of the second diffracted light at the surface of the workpiece SUB is equal to or less than the processing threshold Fth.

[0300] Thus, the fluence F OK m of the first diffracted light irradiated onto the processing point is larger than the processing threshold Fth, and the fluence F NG m of the second diffracted light irradiated onto the non-processing point becomes equal to or less than the processing threshold Fth. Therefore, unnecessary processing can be suppressed and necessary processing can be performed.

[0301] (2) According to the first embodiment, the laser processing processor 53 sets the target value of the fluence F OK m of the first diffracted light, that is, the target fluence F OK mt, and controls adjustment mechanisms such as the attenuator 52. (a) The target fluence F OK mt is larger than the processing threshold Fth. (b) The target fluence F OK mt is equal to or less than the value Fth / R obtained by dividing the processing threshold Fth by the light intensity ratio R, where the light intensity ratio R is the light intensity I NG of the second diffracted light at the surface of the workpiece SUB divided by the light intensity I OK of the first diffracted light at the surface of the workpiece SUB.

[0302] Thus, when setting the target fluence F OK mt of the first diffracted light, by using the light intensity ratio R, not only can the fluence F OK m of the first diffracted light be controlled within a desired range, but also the fluence F NG m of the second diffracted light can be controlled within a desired range.

[0303] Regarding other aspects, the first embodiment is the same as the comparative example.

[0304] 3. Laser processing system that takes into account the deviation of fluence between the first diffracted lights and between the second diffracted lights

[0305] 3.1 Concept

[0306] 3.1.1 Fluence of the first diffracted light and the second diffracted light

[0307] Figure 24 is a bar graph showing an example of the control result in the second embodiment. In the second embodiment, the deviation of fluence between the first diffracted lights converging on the processing point and the deviation of fluence between the second diffracted lights converging on the non-processing point are considered. The diffracted light with the maximum fluence among the first diffracted lights is defined as the first maximum diffracted light, and the fluence of the first maximum diffracted light is set as F OK max. The diffracted light with the minimum fluence among the first diffracted lights is defined as the first minimum diffracted light, and the fluence of the first minimum diffracted light is set as F OK min. The diffracted light with the maximum fluence among the second diffracted lights is defined as the second maximum diffracted light, and the fluence of the second maximum diffracted light is set as F NG max. The diffracted light with the minimum fluence among the second diffracted lights is defined as the second minimum diffracted light, and the fluence of the second minimum diffracted light is set as F NG min.

[0308] Figure 24 The first maximum diffracted light, the first minimum diffracted light, the second maximum diffracted light, and the second minimum diffracted light are arranged on the horizontal axis, and the vertical axis shows the fluence F of each diffracted light at the surface of the workpiece SUB. In the second embodiment, the laser processing processor 53 controls adjustment mechanisms such as the attenuator 52 so that the fluence F OK min of the first minimum diffracted light is greater than the processing threshold Fth, and the fluence F NG max of the second maximum diffracted light becomes equal to or less than the processing threshold Fth.

[0309] 3.1.2 Setting of the target fluence F OK mint

[0310] In the second embodiment, the target fluence F OK mint of the first minimum diffracted light is set as follows. When controlling the fluence F OK min of the first minimum diffracted light to the target fluence F OK mint, the fluences of the first maximum diffracted light, the second maximum diffracted light, and the second minimum diffracted light respectively become values determined according to the light intensity ratio with respect to the first minimum diffracted light.

[0311] Figure 25 is a bar graph showing an example of the target fluence F of the first minimum diffracted light set in the second embodiment. The first minimum diffracted light and the second maximum diffracted light are arranged on the horizontal axis, and the fluence F of each diffracted light at the surface of the workpiece SUB is shown on the vertical axis. OK mint's lower limit

[0312] 3.1.2.1 Target fluence F OK mint's lower limit

[0313] Target fluence F OK mint is set to a value larger than the processing threshold Fth. As a result, the fluence F OK min of the first minimum diffracted light becomes a value larger than the processing threshold Fth. The fluences of the first diffracted lights including the fluence F OK max of the first maximum diffracted light are all equal to or greater than the fluence F OK min of the first minimum diffracted light, and thus also become values larger than the processing threshold Fth.

[0314] 3.1.2.2 Target fluence F OK mint's upper limit

[0315] As shown in the following formula, the value obtained by dividing the light intensity I NG max of the second maximum diffracted light at the surface of the workpiece SUB by the light intensity I OK min of the first minimum diffracted light at the surface of the workpiece SUB is defined as the light intensity ratio R N / O .

[0316] R N / O = I NG max / I OK min

[0317] Target fluence F OK mint is set to a value equal to or less than the value obtained by dividing the processing threshold Fth by the light intensity ratio R N / O i.e., Fth / R N / O By setting the target fluence F OK mint to a value equal to or less than the value Fth / R N / O the fluence F NG max of the second maximum diffracted light becomes a value equal to or less than the processing threshold Fth. The fluences of the second diffracted lights including the fluence F NG min of the second minimum diffracted light are all equal to or less than the fluence F NG max of the second maximum diffracted light, and thus also become values equal to or less than the processing threshold Fth. Additionally, when the target fluence F OK mint is set to a value larger than the processing threshold Fth, the fluence F NGmax becomes the ratio Fth·R N / O a large value.

[0318] 3.1.2.3 Target fluence F OK the range of mint

[0319] According to Figure 25 and its description, if the target fluence F OK is set to the following range for mint, then the fluence F OK of the first minimum diffracted light becomes a value larger than the processing threshold Fth, and the fluence F NG max of the second maximum diffracted light becomes a value equal to or less than the processing threshold Fth.

[0320] Fth < F OK mint ≤ Fth / R N / O

[0321] 3.2 Structure of the laser processing system

[0322] The structure of the laser processing system of the second embodiment is the same as that of the comparative example described with reference to Figure 1 the description.

[0323] 3.3 Measurement of diffractive optical element information

[0324] Figure 26 Schematically shows the structure of the measurement system for measuring the information of the diffractive optical element 63 in the second embodiment. In the optical system including Figure 1 the diffractive optical element 63 and the condenser optical system 67 shown, at a position at a focal length f 67 from the condenser optical system 67, an image sensor 81 is disposed instead of the workpiece SUB. This measurement system can be provided separately from the laser processing apparatus 5 or can be provided inside the laser processing apparatus 5.

[0325] The image sensor 81 is connected to the light intensity measurement processor 83, and the light intensity measurement processor 83 is connected to the data management server 93. The light intensity measurement processor 83 is a processing device including a memory 83a storing a control program and a CPU 83b executing the control program. The light intensity measurement processor 83 is specifically configured or programmed to execute various processes included in the present disclosure.

[0326] The pulsed laser Out incident on the diffractive optical element 63 has the same wavelength λ as the pulsed laser Out output from the laser device 1. The image sensor 81 outputs image data including the light intensity or its time integral value at each position of the light receiving surface. The light intensity measurement processor 83 measures the light intensities of the first diffracted light and the second diffracted light based on the image data output from the image sensor 81.

[0327] The light intensities of the first diffracted light and the second diffracted light are not limited to the measured values obtained using the Figure 26 measurement system shown, and can also be obtained by simulating the diffracted light based on the design data of the diffractive optical element 63.

[0328] Figure 27 FIG. is a flowchart showing the process of light intensity measurement in the second embodiment. Through the following process, the light intensity measurement processor 83 measures the light intensity of the diffracted light and obtains information on the diffractive optical element 63.

[0329] In S901, the light intensity measurement processor 83 measures the light intensity I of the second diffracted light NG . When the number of the second diffracted lights is set to Jmax, the light intensity I of the second diffracted light NG can be expressed as the following data string.

[0330] I NG (1), I NG (2),..., I NG (Jmax)

[0331] In S902, the light intensity measurement processor 83 calculates the following values.

[0332] · The light intensity I of the second maximum diffracted light NG max

[0333] · The total value I of the light intensities I of the second diffracted lights NG NG sum

[0334] The light intensity I of the second maximum diffracted light NG max is the maximum value among the light intensities I of the second diffracted lights NG . The total value I of the light intensities I of the second diffracted lights NG NG sum is the value calculated by I NG (1) + I NG (2) +... + I NG (Jmax).

[0335] In S903, the light intensity measurement processor 83 measures the light intensity I of the first diffracted light OK . When the number of the first diffracted lights is set to Kmax, the light intensity I of the first diffracted light OK can be expressed as the following data string.

[0336] I OK (1), I OK (2),..., I OK (Kmax)

[0337] In S904, the light intensity measurement processor 83 calculates the following values.

[0338] · The light intensity I of the first minimum diffracted light OK min

[0339] · The total value I of the light intensity I of the first diffracted light OK sum OK sum

[0340] The light intensity I of the first minimum diffracted light OK min is the minimum value among the light intensities I of the first diffracted light. The light intensity I of the first diffracted light OK sum is the total value calculated by I OK sum OK sum is calculated by I OK (1) + I OK (2) +... + I OK (Kmax).

[0341] In S905, the light intensity measurement processor 83 calculates the light intensity I of the second maximum diffracted light by the following formula NG max and the light intensity ratio R of the light intensity I of the first minimum diffracted light OK min N / O .

[0342] R N / O = I NG max / I OK min

[0343] In S907, the light intensity measurement processor 83 calculates the total value Isum of the light intensities of the first diffracted light and the second diffracted light by the following formula.

[0344] Isum = I OK sum + I NG sum

[0345] In S908, the light intensity measurement processor 83 saves the following calculated values in the data management server 93.

[0346] · The total value Isum of the light intensities of the first diffracted light and the second diffracted light

[0347] · The light intensity I of the first minimum diffracted light OK min

[0348] · The light intensity I of the second maximum diffracted light NG max and the light intensity ratio R of the light intensity I of the first minimum diffracted light OK min N / O

[0349] 3.4 Processing of the laser processing processor 53

[0350] Figure 28 is a flowchart showing the processing of laser processing in the second embodiment. Regarding the processing of laser processing in the second embodiment, the processing of S300b, S400b, S500b, and S600b is different from the corresponding processing in the first embodiment. The following will refer to Figures 29 - 32 to explain the details of each process.

[0351] 3.4.1 Reading of diffractive optical element information

[0352] Figure 29 is a flowchart showing the details of the process of reading the information of the diffractive optical element 63. Figure 29 The process shown corresponds to Figure 28 the subroutine of S300b.

[0353] In S301, the laser processing processor 53 reads the transmittance T of the diffractive optical element 63 DOE . This is the same as the comparative example.

[0354] In S302b, the laser processing processor 53 reads Figure 27 the following information calculated in

[0355] · The total value of the light intensities of the first diffracted light and the second diffracted light Isum

[0356] · The light intensity I of the first minimum diffracted light OK min

[0357] · The light intensity I of the second maximum diffracted light NG max and the light intensity ratio R of the light intensity I of the first minimum diffracted light OK min N / O

[0358] The total value of the light intensities of the first diffracted light and the second diffracted light Isum and the light intensity I of the first minimum diffracted light OK min are used for reference in Figure 32 the S603b described. The light intensity ratio R N / O is used for reference in Figure 30 the S401b described.

[0359] After S302b, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 28 the process shown.

[0360] 3.4.2 Determination of the target fluence

[0361] Figure 30It is a flowchart showing the details of the process for determining the target fluence F OK mint of the first minimum diffracted light. Figure 30 The process shown corresponds to Figure 28 the subroutine of S400b.

[0362] In S401b, the laser processing processor 53 calculates the fluence F NG max of the second maximum diffracted light by the following formula when the processing threshold Fth is reached for the first minimum diffracted light fluence F OK minth.

[0363] F OK minth = Fth / R N / O

[0364] In S410b, the laser processing processor 53 determines the target fluence F OK mint that satisfies the following formula.

[0365] Fth < F OK mint ≤ Fth / R N / O

[0366] The target fluence F OK mint can also be set to Fth / R as the upper limit value N / O . Thus, it is possible to suppress processing of non-processing points that do not require processing and maximize the efficiency of laser processing. Or, the target fluence F OK mint can also be set to the average value of Fth and Fth / R N / O . Thus, even in the case where there is an unexpected deviation in the pulse energy of the pulsed laser Out, it is possible to avoid processing non-processing points and insufficiently processing processing points.

[0367] After S410b, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 28 the process shown.

[0368] 3.4.3 Determination of the number of irradiation pulses Nm and the repetition frequency f

[0369] Figure 31 It is a flowchart showing the details of the process for determining the number of irradiation pulses Nm and the repetition frequency f in one laser processing. Figure 31 The process shown corresponds to Figure 28 the subroutine of S500b.

[0370] In S501b, the laser processing processor 53 determines the target fluence F OKThe mint and the thickness t determine the number of irradiation pulses Nm. Since the fluence is different between the first minimum diffracted light and the first maximum diffracted light, the processing speed is different. According to the target fluence F of the first minimum diffracted light with the slowest processing speed OK The mint determines the number of irradiation pulses Nm, whereby holes with a sufficient depth can be formed at all the processing points. For example, when the depth of the hole formed at the processing point where the first minimum diffracted light is incident is equal to the thickness t, through holes can be formed at all the processing points.

[0371] In S502, the laser processing processor 53 determines the repetition frequency f suitable for processing. This is the same as in the comparative example.

[0372] After S502, the laser processing processor 53 ends the processing of this flowchart and returns Figure 28 to the processing shown.

[0373] 3.4.4 Adjustment of the Laser Processing System

[0374] Figure 32 is a flowchart showing the details of the process of adjusting the laser processing system according to the target fluence F OK and the mint. Figure 32 The processing shown corresponds to Figure 28 the subroutine of S600b of

[0375] Regarding Figure 32 the processing shown, the calculation formula used to set the transmittance Ta of the attenuator 52 in S603b is different from that of Figure 23 the first embodiment shown. The energy of each pulse of the first minimum diffracted light is represented by the following equation.

[0376] (I OK min / Isum)·Et·Ta·T0·T DOE =F OK mint·S

[0377] Therefore, the transmittance Ta of the attenuator 52 is calculated by the following formula.

[0378] Ta=F OK mint·S·(Isum / I OK min) / (Et·T0·T DOE )

[0379] Regarding other aspects, Figure 32 the processing shown is the same as Figure 23 the processing shown.

[0380] 3.5 Function

[0381] (3)According to the second embodiment, there are respectively fluence F OK m and F NG m deviations between the first diffracted lights and between the second diffracted lights. The laser processing processor 53 controls the adjustment mechanism to satisfy the following conditions. (a) The fluence F OK m of the first minimum diffracted light with the minimum fluence F OK min in the first diffracted lights is greater than the processing threshold Fth. (b) The fluence F NG m of the second maximum diffracted light with the maximum fluence F NG max in the second diffracted lights is below the processing threshold Fth.

[0382] Thus, in the case where there are fluence deviations between multiple diffracted lights, by determining the condition of the fluence F OK min of the first minimum diffracted light, it is also possible to make the fluence F OK m of the first diffracted lights irradiated to multiple processing points greater than the processing threshold Fth. In addition, by determining the condition of the fluence F NG max of the second maximum diffracted light, it is possible to make the fluence F NG m of the second diffracted lights irradiated to multiple non-processing points below the processing threshold Fth. Therefore, unnecessary processing can be suppressed and necessary processing can be performed.

[0383] (4)According to the second embodiment, the laser processing processor 53 sets the target value of the fluence F OK min of the first minimum diffracted light, that is, the target fluence F OK mint, and controls adjustment mechanisms such as the attenuator 52. (a) The target fluence F OK mint is greater than the processing threshold Fth. (b) The target fluence F OK mint is the value Fth / R N / O obtained by dividing the processing threshold Fth by the light intensity ratio R N / O , and this light intensity ratio R N / O is the light intensity I NG max of the second maximum diffracted light divided by the light intensity I OK min of the first minimum diffracted light.

[0384] Thus, in the case where there are fluence deviations between multiple diffracted lights, by setting the target fluence F OK mint of the first minimum diffracted light, it is possible to control the fluence F OK m of the first diffracted lights irradiated to multiple processing points within a desired range. In addition, when setting the target fluence F OK mint of the first minimum diffracted light, the light intensity ratio R N / Ocan also control the fluence F of the second diffracted light irradiated on a plurality of non-processing points within a desired range. NG m within a desired range.

[0385] (5) According to the second embodiment, the laser processing processor 53 calculates parameters such as the transmittance Ta of the attenuator 52, and controls adjustment mechanisms such as the attenuator 52, which is used to adjust the pulse energy of the pulsed laser Out incident on the diffractive optical element 63. The parameter is calculated based on the ratio of the sum value Isum of the light intensities of the first diffracted light and the second diffracted light to the light intensity I of the first minimum diffracted light OK min and the target fluence F OK mint.

[0386] Thus, in the case where there is a deviation in fluence among a plurality of first diffracted lights, or in the case where a part of the pulse energy of the pulsed laser Out is discarded as the energy of the second diffracted light, by using the ratio of the sum value Isum of the light intensities of the first diffracted light and the second diffracted light to the light intensity I of the first minimum diffracted light OK min, it is also possible to set the target fluence F of the first minimum diffracted light OK mint.

[0387] In other aspects, the second embodiment is the same as the first embodiment.

[0388] 4. Laser processing system considering the pulse energy deviation of the pulsed laser output from the laser device

[0389] 4.1 Concept

[0390] 4.1.1 Fluence of the first diffracted light and the second diffracted light

[0391] Figure 33 is a bar graph showing an example of the control result in a modification of the second embodiment. In the modification of the second embodiment, the pulse energy deviation δE of the pulsed laser Out output from the laser device 1 is considered. When the pulse energy of the pulsed laser Out varies, the fluences of the first maximum diffracted light, the first minimum diffracted light, the second maximum diffracted light, and the second minimum diffracted light all vary according to the same pulse energy deviation δE. The pulse energy deviation δE is calculated based on the standard deviation and the average value of the pulse energies of a plurality of pulses included in the pulsed laser Out. For example, the pulse energy deviation δE is a value obtained by dividing a value that is 1 time, 2 times, or 3 times the standard deviation by the average value.

[0392] Figure 33The horizontal axis is configured with a first maximum diffracted light, a first minimum diffracted light, a second maximum diffracted light, and a second minimum diffracted light, and the vertical axis shows the fluence F of each diffracted light at the surface of the workpiece SUB. The fluence F of each diffracted light varies as follows according to the pulse energy deviation δE.

[0393] The range of variation of the fluence F OK min of the first minimum diffracted light based on the pulse energy deviation δE is set as the first variation range. The first variation range can use the target fluence F OK mint of the first minimum diffracted light is expressed by the following formula.

[0394] F OK mint·(1 - δE) ≤ F OK min ≤ F OK mint·(1 + δE)

[0395] The range of variation of the fluence F NG max of the second maximum diffracted light based on the pulse energy deviation δE is set as the second variation range. The second variation range can use the target fluence F NG maxt of the second maximum diffracted light is expressed by the following formula.

[0396] F NG maxt·(1 - δE) ≤ F NG max ≤ F NG maxt·(1 + δE)

[0397] The target fluence F NG maxt of the second maximum diffracted light is the target fluence F OK mint of the first minimum diffracted light multiplied by the light intensity ratio R N / O and obtained value. The target fluence F NG maxt of the second maximum diffracted light is a convenient name used to compare with the target fluence F OK mint of the first minimum diffracted light, and its value may not be used as the target value of the fluence.

[0398] The fluence F OK max of the first maximum diffracted light and the fluence F NG min of the second minimum diffracted light also vary according to the pulse energy deviation δE.

[0399] In a modification of the second embodiment, the laser processing processor 53 controls adjustment mechanisms such as the attenuator 52 so that the minimum value F OK mint·(1 - δE) of the first variation range of the fluence F OK min of the first minimum diffracted light is greater than the processing threshold Fth, and the fluence FNG The maximum value F of the second variation range of max NG maxt·(1 + δE) becomes less than or equal to the processing threshold Fth.

[0400] 4.1.2 Target fluence F OK Setting of mint

[0401] Figure 34 It shows the target fluence F of the first minimum diffracted light set in the modification of the second embodiment OK A bar graph of an example of mint. The first minimum diffracted light and the second maximum diffracted light are arranged on the horizontal axis, and the fluence F of each diffracted light at the surface of the workpiece SUB is shown on the vertical axis.

[0402] 4.1.2.1 Target fluence F OK The lower limit of mint

[0403] Target fluence F OK mint is set so that the fluence F of the first minimum diffracted light OK The minimum value F of the first variation range of min OK mint·(1 - δE) is a value greater than the processing threshold Fth. Therefore, the following relationship is given.

[0404] Fth < F OK mint·(1 - δE)

[0405] Based on the above inequality, the following relationship representing the target fluence F OK The lower limit of mint is derived.

[0406] Fth / (1 - δE) < F OK mint

[0407] As shown in the following formula, the left side Fth / (1 - δE) of the above formula is equivalent to the value obtained by adding Fth·δE / (1 - δE) to the processing threshold Fth.

[0408] Fth / (1 - δE) = Fth + Fth·δE / (1 - δE)

[0409] Fth·δE / (1 - δE) is equivalent to the first variation amplitude in the present disclosure.

[0410] By setting the target fluence F OK The lower limit of mint, the fluence F of the first minimum diffracted light OK The minimum value F of the first variation range of min OK mint·(1 - δE) becomes a value greater than the processing threshold Fth. Including the fluence F of the first maximum diffracted light OKThe fluence of the first diffracted light of max is the fluence F of the first minimum diffracted light OK The minimum value F of the first variation range of min OK Above mint·(1 - δE), so it also becomes a value larger than the processing threshold Fth

[0411] 4.1.2.2 Target fluence F OK The upper limit of mint

[0412] Target fluence F OK mint is set so that the fluence F of the second maximum diffracted light NG The maximum value F of the second variation range of max NG maxt·(1 + δE) becomes below the processing threshold Fth. Thus, the following relationship is given

[0413] F NG maxt·(1 + δE) ≤ Fth

[0414] F NG maxt is the target fluence F for the first minimum diffracted light OK mint multiplied by the light intensity ratio R N / O And the obtained value. Therefore, according to the above inequality, the relationship representing the upper limit of the target fluence F OK Of mint is derived

[0415] F OK mint ≤ (Fth / R N / O ) / (1 + δE)

[0416] As shown in the following formula, the right side of the above formula (Fth / R N / O ) / (1 + δE) is equivalent to the value obtained by dividing the processing threshold Fth by the light intensity ratio R N / O And getting the value Fth / R N / O Subtracting the value obtained by (Fth / R N / O )·δE / (1 + δE)

[0417] (Fth / R N / O ) / (1 + δE) = Fth / R N / O -(Fth / R N / O )·δE / (1 + δE)

[0418] (Fth / R N / O )·δE / (1 + δE) is equivalent to the second variation amplitude in this disclosure

[0419] By setting the upper limit of the target fluence F of the first minimum diffracted light OK mint, the fluence F of the second maximum diffracted light NGThe maximum value F of the second variation range of max NG maxt·(1 + δE) becomes a value equal to or less than the processing threshold Fth. The fluence F including the second minimum diffracted light NG The fluences of the second diffracted light of min are all the fluence F of the second maximum diffracted light NG The maximum value F of the second variation range of max NG is equal to or less than maxt·(1 + δE), and thus also becomes a value equal to or less than the processing threshold Fth. Additionally, by setting the target fluence F OK mint to a value greater than Fth / (1 - δE), when the fluence F OK The minimum value F of the first variation range of min OK mint·(1 - δE) is set to a value greater than the processing threshold Fth, the fluence F NG The minimum value F of the second variation range of max NG maxt·(1 - δE) becomes a value equal to the ratio Fth·R N / O greater value.

[0420] 4.1.2.3 Target fluence F OK The range of mint

[0421] According to Figure 34 and its description, if the target fluence F OK mint is set within the following range, then the entire first variation range of the fluence of the first diffracted light becomes a value greater than the processing threshold Fth, and the entire second variation range of the fluence of the second diffracted light becomes a value equal to or less than the processing threshold Fth.

[0422] Fth / (1 - δE) < F OK mint ≤ (Fth / R N / O ) / (1 + δE)

[0423] 4.2 Structure of the laser processing system

[0424] The structure of the laser processing system according to the modified example of the second embodiment is the same as the structure of the comparative example described with reference to Figure 1 description.

[0425] 4.3 Processing of the laser processing processor 53

[0426] Figure 35 is a flowchart showing the processing of laser processing in the modified example of the second embodiment. Regarding the processing of laser processing in the modified example of the second embodiment, the processing of S100c and S400c is different from the corresponding processing in the second embodiment. The following refers to Figure 36 and Figure 37 to explain the details of each processing.

[0427] 4.3.1 Reading in Information of Laser Processing System

[0428] Figure 36 is a flowchart showing details of the process of reading in information of the laser processing system. Figure 36 The process shown corresponds to Figure 35 the subroutine of S100c of

[0429] In S101 to S103, the laser processing processor 53 reads in the transmittance T0, the number of holes P, and the irradiation area S. This is the same as in the comparative example.

[0430] In S104c, the laser processing processor 53 reads in the value of the pulse energy deviation δE. The pulse energy deviation δE is used for reference in Figure 37 the S410c described

[0431] After S104c, the laser processing processor 53 ends the process of this flowchart and returns to Figure 35 the process shown.

[0432] 4.3.2 Determination of Target Fluence

[0433] Figure 37 is a flowchart showing details of the process of determining the target fluence F OK mint of the first minimum diffracted light. Figure 37 The process shown corresponds to Figure 35 the subroutine of S400c of

[0434] In S401b, the laser processing processor 53 calculates the fluence F NG max of the second maximum diffracted light when the processing threshold Fth is reached, and the fluence F OK minth of the first minimum diffracted light. This is the same as in the second embodiment.

[0435] In S410c, the laser processing processor 53 determines the target fluence F OK mint that satisfies the following formula.

[0436] Fth / (1 - δE) < F OK mint ≤ (Fth / R N / O ) / (1 + δE)

[0437] The target fluence F OK mint can also be set to (Fth / R N / O ) / (1 + δE) as the upper limit value. Thus, it is possible to suppress processing of non-processing points that do not require processing and maximize the efficiency of laser processing. Or, the target fluence F OKThe mint can also be set to the average value of Fth / (1 - δE) and (Fth / R N / O ) / (1 + δE). Thus, even when there are deviations in the pulse energy of the pulsed laser Out beyond expectations, it is possible to avoid processing non-processing points and insufficiently processing the processing points that need to be processed.

[0438] After S410c, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 35 the processing shown.

[0439] 4.4 Function

[0440] (6) According to the modification of the second embodiment, there are respectively fluence F OK m and F NG m deviations between the first diffracted light and the second diffracted light. The laser processing processor 53 controls the adjustment mechanism to meet the following conditions. (a) The minimum value F OK m of the fluence F OK min of the first minimum diffracted light, the minimum value F OK mint·(1 - δE) of the first variation range based on the pulse energy deviation δE of the pulsed laser Out incident on the diffractive optical element 63 is greater than the processing threshold Fth. (b) The maximum value F NG m of the fluence F NG max of the second maximum diffracted light, the maximum value F NG maxt·(1 + δE) of the second variation range based on the pulse energy deviation δE is below the processing threshold Fth.

[0441] Thus, not only when there are fluence deviations between multiple diffracted lights, but also when there is a pulse energy deviation δE in the pulsed laser Out, it is possible to make the overall variation range of the fluence F OK m of the first diffracted light irradiated onto multiple processing points larger than the processing threshold Fth. In addition, it is possible to make the overall variation range of the fluence F NG m of the second diffracted light irradiated onto multiple non-processing points below the processing threshold Fth. Therefore, it is possible to suppress unnecessary processing and perform necessary processing.

[0442] (7) According to the modification of the second embodiment, the laser processing processor 53 sets the target value, i.e., the target fluence F OK min, of the first minimum diffracted light as follows, and controls adjustment mechanisms such as the attenuator 52. (a) The target fluence F OK mint, OKThe value obtained by adding the machining threshold Fth of the mint comparison to the first variation range Fth·δE / (1 - δE) representing the pulse energy deviation δE is larger than Fth / (1 - δE). (b) Target fluence F OK The mint is from the value Fth / R N / O subtracting the second variation range (Fth / R N / O )·δE / (1 + δE) obtained from the pulse energy deviation δE, and the value (Fth / R N / O ) / (1 + δE) is below this, and this light intensity ratio R N / O is the light intensity I NG max of the second maximum diffracted light divided by the light intensity I OK min of the first minimum diffracted light, and this value Fth / R N / O is obtained by dividing the machining threshold Fth by the light intensity ratio R N / O .

[0443] Thus, not only in the case where there is a fluence deviation between multiple diffracted lights, but also in the case where there is a pulse energy deviation δE in the pulsed laser Out, the overall variation range of the fluence F OK m of the first diffracted light irradiated to multiple machining points can be controlled within a desired range. In addition, when setting the target fluence F OK mint of the first minimum diffracted light, using the light intensity ratio R N / O , the overall variation range of the fluence F NG m of the second diffracted light irradiated to multiple non-machining points can be controlled within a desired range.

[0444] In other respects, the modification of the second embodiment is the same as the second embodiment.

[0445] 5. Laser processing system considering the fluence upper limit value

[0446] 5.1 Concept

[0447] 5.1.1 Fluence of the first diffracted light and the second diffracted light

[0448] Figure 38 is a bar graph showing an example of the control result in the third embodiment. In the third embodiment, the upper limit value of the fluence of the first diffracted light converging on the machining point is considered. For example, when the fluence is too high, sometimes unintended cracks may occur in the workpiece SUB.

[0449] Figure 38The horizontal axis is configured with a first maximum diffracted light, a first minimum diffracted light, a second maximum diffracted light, and a second minimum diffracted light, and the vertical axis shows the fluence F of each diffracted light at the surface of the workpiece SUB. Similar to the second embodiment, the laser processing processor 53 controls adjustment mechanisms such as the attenuator 52 so that the fluence F OK min of the first minimum diffracted light is greater than the processing threshold Fth, and the fluence F NG max of the second maximum diffracted light becomes equal to or less than the processing threshold Fth. Further, in the third embodiment, the laser processing processor 53 controls adjustment mechanisms such as the attenuator 52 so that the fluence F OK max of the first maximum diffracted light becomes equal to or less than the fluence upper limit value Fcr. That is, the adjustment mechanism is controlled to simultaneously satisfy the following three conditions.

[0450] F OK min > Fth

[0451] F NG max ≤ Fth

[0452] F OK max ≤ Fcr

[0453] Figure 39 is a graph showing an example of the definition of the fluence upper limit value Fcr. Figure 39 The horizontal axis of is the fluence of the diffracted light. Diffracted light with different fluences is irradiated onto a plurality of workpieces SUB, and it is determined whether cracks are generated. The fluence of the diffracted light with the minimum fluence among the diffracted lights for which cracks are generated is the fluence upper limit value Fcr. The possibility of generating cracks is low when irradiating diffracted light with a fluence less than the fluence upper limit value Fcr, and the possibility of generating cracks is high when irradiating diffracted light with a fluence equal to or greater than the fluence upper limit value Fcr.

[0454] 5.1.2 Target fluence F OK mint setting

[0455] Figure 40 and Figure 41 are bar graphs showing examples of the target fluence F OK mint of the first minimum diffracted light set in the third embodiment. In Figure 40 and Figure 41 , the horizontal axis is configured with the first maximum diffracted light, the first minimum diffracted light, and the second maximum diffracted light, and the vertical axis shows the fluence F of each diffracted light at the surface of the workpiece SUB.

[0456] 5.1.2.1 Lower limit of the target fluence F OK mint

[0457] Similar to the second embodiment, the target fluence F OKmint is set to a value larger than the processing threshold Fth. As a result, the fluence F OK min of the first minimum diffracted light becomes a value larger than the processing threshold Fth. The fluence of the first diffracted light including the fluence F OK max of the first maximum diffracted light is all above the fluence F OK min of the first minimum diffracted light. Therefore, it also becomes a value larger than the processing threshold Fth.

[0458] 5.1.2.2 Target fluence F OK Upper limit of mint (1)

[0459] Similar to the second embodiment, the target fluence F OK mint is set to the value Fth / R obtained by dividing the processing threshold Fth by the light intensity ratio R N / O and below. By setting the target fluence F N / O mint to a value below the value Fth / R OK , the fluence F N / O max of the second maximum diffracted light becomes a value below the processing threshold Fth. The fluence of the second diffracted light including the fluence F NG min of the second minimum diffracted light is all below the fluence F NG max of the second maximum diffracted light. Therefore, it also becomes a value below the processing threshold Fth. Additionally, when the target fluence F NG mint is set to a value larger than the processing threshold Fth, the fluence F OK max of the second maximum diffracted light becomes a value larger than the ratio value Fth·R NG . N / O Large value.

[0460] 5.1.2.3 Target fluence F OK Upper limit of mint (2)

[0461] As shown in the following formula, the light intensity I OK max of the first maximum diffracted light at the surface of the workpiece SUB is divided by the light intensity I OK min of the first minimum diffracted light at the surface of the workpiece SUB, and the resulting value is set as the light intensity ratio R O / O .

[0462] R O / O = I OK max / I OK min

[0463] The fluence F OK max of the first maximum diffracted light becomes the fluence F OK mincr of the first minimum diffracted light when the fluence upper limit value Fcr is given by the following formula.

[0464] F OK mincr = Fcr / R O / O

[0465] Target fluence F OK mint is set to the value obtained by dividing the fluence upper limit value Fcr by the light intensity ratio R O / O That is, the value Fcr / R O / O The following value. By setting the target fluence F OK mint to the value Fcr / R O / O The following value, the fluence F of the first maximum diffracted light OK max becomes a value below the fluence upper limit value Fcr. The fluence F of the first diffracted light including the first minimum diffracted light OK min of the first diffracted light is all below the fluence F of the first maximum diffracted light OK max, so it also becomes a value below the fluence upper limit value Fcr.

[0466] 5.1.2.4 Target fluence F OK Range of mint

[0467] As described above, in the third embodiment, the target fluence F OK There are two upper limits of mint. That is, the target fluence F OK mint is set to the value Fth / R N / O Below, and the value Fcr / R O / O Below.

[0468] In the case where the value Fcr / R O / O Ratio Fth / R N / O Is large, that is, the fluence upper limit value Fcr ratio (Fth / R N / O )·R O / O Is large, if the target fluence F OK mint is made the value Fth / R N / O Below, then the value Fcr / R O / O Can also be not considered (refer to Figure 40 ).

[0469] In this case, similar to the second embodiment, if the target fluence F OK mint is set to the following range, then the fluence F of the first minimum diffracted light OK min is greater than the processing threshold Fth, the fluence F of the first maximum diffracted light OK max becomes a value below the fluence upper limit value Fcr, and the fluence F of the second maximum diffracted light NG max becomes a value below the processing threshold Fth.

[0470] Fth < FOK mint ≤ Fth / R N / O

[0471] In other words, when the ratio of the fluence upper limit value Fcr to (Fth / R N / O )·R O / O is large, it is only necessary to satisfy the following two conditions simultaneously.

[0472] F OK min > Fth

[0473] F NG max ≤ Fth

[0474] When the value of Fcr / R O / O the ratio of Fth / R N / O is small, that is, when the ratio of the fluence upper limit value Fcr to (Fth / R N / O )·R O / O is small, if the target fluence F OK mint becomes a value below Fcr / R O / O then the value of Fth / R N / O (see Figure 41 ) can also be not considered. The value (Fth / R N / O )·R O / O corresponds to the fluence F NG max of the second maximum diffracted light when the fluence F OK max of the first maximum diffracted light becomes the processing threshold Fth.

[0475] In this case, if the target fluence F OK mint is set within the following range, then the fluence F OK min of the first minimum diffracted light is greater than the processing threshold Fth, the fluence F OK max of the first maximum diffracted light becomes a value below the fluence upper limit value Fcr, and the fluence F NG max of the second maximum diffracted light becomes a value below the processing threshold Fth.

[0476] Fth < F OK mint ≤ Fcr / R O / O

[0477] In other words, when the ratio of the fluence upper limit value Fcr to (Fth / R N / O )·R O / O is small, it is only necessary to satisfy the following two conditions simultaneously.

[0478] F OK min > Fth

[0479] F OK max ≤ Fcr

[0480] 5.2 Structure of the Laser Processing System

[0481] The structure of the laser processing system according to the third embodiment is the same as that of the comparative example described with reference to Figure 1 explanation.

[0482] 5.3 Measurement of Diffractive Optical Element Information

[0483] Figure 42 is a flowchart showing the process of light intensity measurement in the third embodiment. In the third embodiment, the structure of the measurement system for measuring the information of the diffractive optical element 63 is the same as that of the second embodiment described with reference to Figure 26 explanation. Regarding Figure 42 the process shown, in addition to the processes of S904d and S908d being different from the corresponding processes in the second embodiment, the process of S906d is also added.

[0484] In S904d, the light intensity measurement processor 83 calculates the following values.

[0485] · Light intensity I of the first maximum diffracted light OK max

[0486] · Light intensity I of the first minimum diffracted light OK min

[0487] · Total value I of the light intensity I of the first diffracted light OK of OK sum

[0488] The light intensity I of the first maximum diffracted light OK max is the maximum value among the light intensities I of the first diffracted light OK .

[0489] After S905 and before S907, in S906d, the light intensity measurement processor 83 calculates the light intensity ratio R of the light intensity I of the first maximum diffracted light OK max to the light intensity I of the first minimum diffracted light OK min O / O .

[0490] R O / O = I OK max / I OK min

[0491] In S908d, the light intensity measurement processor 83 saves the following calculated values in the data management server 93.

[0492] · Total value Isum of the light intensities of the first diffracted light and the second diffracted light

[0493] · The light intensity I of the first minimum diffracted light OK min

[0494] · The light intensity I of the second maximum diffracted light NG max and the light intensity I of the first minimum diffracted light OK The light intensity ratio R of min N / O

[0495] · The light intensity I of the first maximum diffracted light OK max and the light intensity I of the first minimum diffracted light OK The light intensity ratio R of min O / O

[0496] 5.4 Processing of the laser processing processor 53

[0497] Figure 43 is a flowchart showing the processing of the laser processing in the third embodiment. Regarding the processing of the laser processing in the third embodiment, the processing of S200d, S300d, and S400d is different from the corresponding processing in the second embodiment. The following refers to Figures 44 - 46 to explain the details of each processing.

[0498] 5.4.1 Reading of workpiece information

[0499] Figure 44 is a flowchart showing the details of the processing of reading the information of the workpiece SUB. Figure 44 The processing shown corresponds to Figure 43 the subroutine of S200d.

[0500] In S201 and S202, the laser processing processor 53 reads the processing threshold Fth and the thickness t. This is the same as in the comparative example.

[0501] In S203d, the laser processing processor 53 reads the fluence upper limit value Fcr. The fluence upper limit value Fcr is used for reference in Figure 46 the S405d and S412d described.

[0502] After S203d, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 43 the processing shown.

[0503] 5.4.2 Reading of diffractive optical element information

[0504] Figure 45 is a flowchart showing the details of the processing of reading the information of the diffractive optical element 63. Figure 45 The processing shown corresponds to Figure 43 the subroutine of S300d.

[0505] In S301, the laser processing processor 53 reads the transmittance T of the diffractive optical element 63 DOE . This is the same as the comparative example.

[0506] In S302d, the laser processing processor 53 reads the Figure 42 following information calculated in

[0507] · The total value Isum of the light intensities of the first diffracted light and the second diffracted light

[0508] · The light intensity I of the first minimum diffracted light OK min

[0509] · The light intensity I of the second maximum diffracted light NG max and the light intensity ratio R of the light intensity I of the first minimum diffracted light OK min N / O

[0510] · The light intensity I of the first maximum diffracted light OK max and the light intensity ratio R of the light intensity I of the first minimum diffracted light OK min O / O

[0511] The light intensity ratio R O / O is used for reference in Figure 46 the S403d and S412d described.

[0512] After S302d, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 43 the processing shown.

[0513] 5.4.3 Determination of the target fluence

[0514] Figure 46 is a flowchart showing the details of the process for determining the target fluence F OK mint of the first minimum diffracted light. Figure 46 The process shown is equivalent to Figure 43 the subroutine of S400d in

[0515] In S401b, the laser processing processor 53 calculates the fluence F of the second maximum diffracted light NG max when it becomes the processing threshold Fth, and the fluence F of the first minimum diffracted light OK minth. This is the same as the second embodiment described with reference to Figure 30 .

[0516] In S403d, the laser processing processor 53 calculates the fluence F of the second maximum diffracted light by the following formula NGThe fluence F of the first maximum diffracted light when max becomes the processing threshold Fth OK maxth.

[0517] F OK maxth = F OK minth·R O / O

[0518] =(Fth / R N / O )·R O / O

[0519] In S405d, the laser processing processor 53 compares the fluence F of the second maximum diffracted light NG The fluence F of the first maximum diffracted light when max becomes the processing threshold Fth OK maxth with the fluence upper limit value Fcr. When the fluence F OK maxth is less than or equal to the fluence upper limit value Fcr (F OK maxth ≤ Fcr), the laser processing processor 53 causes the process to proceed to S410b. When the fluence F OK maxth is greater than the fluence upper limit value Fcr (F OK maxth > Fcr), the laser processing processor 53 causes the process to proceed to S412d.

[0520] In S410b, the laser processing processor 53 determines the target fluence F that satisfies the following equation in the same manner as in the second embodiment OK mint (refer to Figure 40 ).

[0521] Fth < F OK mint ≤ Fth / R N / O

[0522] In S412d, the laser processing processor 53 determines the target fluence F that satisfies the following equation OK mint (refer to Figure 41 ).

[0523] Fth < F OK mint ≤ Fcr / R O / O

[0524] The target fluence F OK mint can also be set to Fcr / R as the upper limit value O / O . Thus, it is possible to suppress processing of non-processing points that do not require processing and maximize the efficiency of laser processing. Alternatively, the target fluence F OK mint can also be set to the value between Fth and Fcr / R O / OThe average value. Thus, even when there is a deviation in the pulse energy of the pulsed laser Out beyond what is envisioned, it is possible to avoid processing non-processing points and to ensure sufficient processing of the processing points that need to be processed.

[0525] After S410b or S412d, the laser processing processor 53 ends the processing of this flowchart and returns Figure 43 to the processing shown.

[0526] 5.5 Function

[0527] (8) According to the third embodiment, there are respectively fluence F OK m and F NG m deviations between the first diffracted light and the second diffracted light. The laser processing processor 53 controls the adjustment mechanism to meet the following conditions. (a) The fluence F OK m of the first minimum diffracted light with the minimum fluence F OK min in the first diffracted light is greater than the processing threshold Fth. (b) The fluence F NG m of the second maximum diffracted light with the maximum fluence F NG max in the second diffracted light is below the processing threshold Fth. (c) The fluence F OK m of the first maximum diffracted light with the maximum fluence F OK max in the first diffracted light is below the fluence upper limit value Fcr.

[0528] Thus, when there is a fluence deviation between multiple diffracted lights, by determining the condition for the fluence F OK max of the first maximum diffracted light, it is also possible to make the fluence F OK m of the first diffracted light irradiated onto multiple processing points below the fluence upper limit value Fcr. Therefore, it is possible not only to suppress unnecessary processing and perform necessary processing, but also to suppress adverse conditions such as breakage of the workpiece SUB.

[0529] (9) According to the third embodiment, the laser processing processor 53 compares the fluence F NG max of the second maximum diffracted light when it becomes the processing threshold Fth with the fluence upper limit value Fcr. OK maxth of the first maximum diffracted light.

[0530] When the fluence upper limit value Fcr is greater than the fluence F NG max of the first maximum diffracted light when the fluence F OK max of the second maximum diffracted light becomes the processing threshold Fth, the laser processing processor 53 controls the adjustment mechanism to meet the following conditions. (a) The fluence F OKThe fluence F of the first minimum diffracted light is greater than the processing threshold Fth. (b) The fluence F of the second maximum diffracted light NG max is below the processing threshold Fth.

[0531] When the upper limit value of fluence Fcr is smaller than the fluence F of the second maximum diffracted light NG max and the fluence F of the first maximum diffracted light when the second maximum diffracted light reaches the processing threshold Fth OK maxth, the laser processing processor 53 controls the adjustment mechanism to satisfy the following conditions. (a) The fluence F of the first minimum diffracted light OK min is greater than the processing threshold Fth. (c) The fluence F of the first maximum diffracted light OK max is below the upper limit value of fluence Fcr.

[0532] Thus, according to the comparison result between the fluence F of the first maximum diffracted light OK maxth and the upper limit value of fluence Fcr, one of condition (b) and condition (c) can be omitted to control the adjustment mechanism, which can simplify the control.

[0533] (10) According to the third embodiment, the laser processing processor 53 sets the target value of the fluence F of the first minimum diffracted light, that is, the target fluence F OK mint, and controls the adjustment mechanism such as the attenuator 52. (a) The target fluence F OK mint is greater than the processing threshold Fth. (b) The target fluence F OK mint is the value Fth / R obtained by dividing the processing threshold Fth by the light intensity ratio R OK N / O Hereinafter, this light intensity ratio R N / O N / O is obtained by dividing the light intensity I of the second maximum diffracted light NG max by the light intensity I of the first minimum diffracted light OK min. (c) The target fluence F OK mint is the value Fcr / R obtained by dividing the upper limit value of fluence Fcr by the light intensity ratio R O / O O / O Hereinafter, this light intensity ratio R O / O is obtained by dividing the light intensity I of the first maximum diffracted light OK max by the light intensity I of the first minimum diffracted light OK min.

[0534] Thus, when there is a fluence deviation among multiple first diffracted lights, when setting the target fluence F of the first minimum diffracted light OK mint, by using the light intensity ratio R O / O , it is also possible to make the fluence F of the first diffracted light irradiated to multiple processing points​​​OK The m is controlled within a desired range to suppress defects such as breakage of the workpiece SUB.

[0535] (11) According to the third embodiment, the laser processing processor 53 compares the fluence F NG max of the first maximum diffracted light when the fluence F of the second maximum diffracted light becomes the processing threshold Fth OK maxth with the fluence upper limit value Fcr.

[0536] When the fluence upper limit value Fcr is larger than the fluence F of the first maximum diffracted light when the fluence F of the second maximum diffracted light becomes the processing threshold Fth NG maxth, the laser processing processor 53 sets the target value of the fluence F of the first minimum diffracted light, that is, the target fluence F OK mint, and controls adjustment mechanisms such as the attenuator 52. (a) The target fluence F OK mint is larger than the processing threshold Fth. (b) The target fluence F OK mint is the value Fth / R obtained by dividing the processing threshold Fth by the light intensity ratio R OK as follows. OK mint is the value Fth / R obtained by dividing the processing threshold Fth by the light intensity ratio R N / O as follows. N / O as follows.

[0537] When the fluence upper limit value Fcr is smaller than the fluence F of the first maximum diffracted light when the fluence F of the second maximum diffracted light becomes the processing threshold Fth NG maxth, the laser processing processor 53 sets the target fluence F OK mint as follows and controls adjustment mechanisms such as the attenuator 52. (a) The target fluence F OK mint is larger than the processing threshold Fth. (c) The target fluence F OK mint is the value Fcr / R obtained by dividing the fluence upper limit value Fcr by the light intensity ratio R OK as follows. O / O as follows. O / O as follows.

[0538] Thus, according to the comparison result between the fluence F of the first maximum diffracted light OK maxth and the fluence upper limit value Fcr, it is possible to set the target fluence F OK mint by omitting one of condition (b) and condition (c), thereby simplifying the control.

[0539] In other respects, the third embodiment is the same as the second embodiment.

[0540] 6. Laser processing system considering the fluence upper limit value and the pulse energy deviation of the pulsed laser output from the laser device

[0541] 6.1 Concept

[0542] 6.1.1 Fluence of the First Diffracted Light and the Second Diffracted Light

[0543] Figure 47 is a bar graph showing an example of the control result in a modified example of the third embodiment. In the modified example of the third embodiment, the pulse energy deviation δE of the pulsed laser Out output from the laser device 1 is considered.

[0544] Figure 47 The horizontal axis has the first maximum diffracted light, the first minimum diffracted light, the second maximum diffracted light, and the second minimum diffracted light, and the vertical axis shows the fluence F of each diffracted light at the surface of the workpiece SUB. The fluence F of each diffracted light varies as follows according to the pulse energy deviation δE.

[0545] Regarding the fluence F OK min of the first minimum diffracted light, the variation range based on the pulse energy deviation δE is set as the first variation range. The first variation range can use the target fluence F OK mint of the first minimum diffracted light and is represented by the following formula.

[0546] F OK mint·(1 - δE) ≤ F OK min ≤ F OK mint·(1 + δE)

[0547] Regarding the fluence F NG max of the second maximum diffracted light, the variation range based on the pulse energy deviation δE is set as the second variation range. The second variation range can use the target fluence F NG maxt of the second maximum diffracted light and is represented by the following formula.

[0548] F NG maxt·(1 - δE) ≤ F NG max ≤ F NG maxt·(1 + δE)

[0549] The target fluence F NG maxt of the second maximum diffracted light is the value obtained by multiplying the target fluence F OK mint of the first minimum diffracted light by the light intensity ratio R N / O and is obtained.

[0550] Regarding the fluence F OK max of the first maximum diffracted light, the variation range based on the pulse energy deviation δE is set as the third variation range. The third variation range can use the target fluence F OK maxt of the first maximum diffracted light and is represented by the following formula.

[0551] F OK maxt·(1 - δE) ≤ F OK max ≤ F OK maxt·(1 + δE)

[0552] The target fluence F of the first maximum diffracted light OK maxt is the target fluence F of the first minimum diffracted light OK mint multiplied by the light intensity ratio R O / O and the resulting value.

[0553] The fluence F of the second minimum diffracted light NG min also varies according to the pulse energy deviation δE in the same way.

[0554] Similar to the modification of the second embodiment, the laser processing processor 53 controls adjustment mechanisms such as the attenuator 52 so that the minimum value F of the first variation range of the fluence F OK min of the first minimum diffracted light OK mint·(1 - δE) is greater than the processing threshold Fth, and the maximum value F of the second variation range of the fluence F NG max of the second maximum diffracted light NG maxt·(1 + δE) becomes below the processing threshold Fth. Furthermore, in the modification of the third embodiment, the laser processing processor 53 controls adjustment mechanisms such as the attenuator 52 so that the maximum value F of the third variation range of the fluence F OK max of the first maximum diffracted light OK maxt·(1 + δE) becomes below the fluence upper limit value Fcr.

[0555] 6.1.2 Target fluence F OK Setting of mint

[0556] Figure 48 is a bar graph showing an example of the target fluence F OK mint of the first minimum diffracted light set in the modification of the third embodiment. The first maximum diffracted light, the first minimum diffracted light, and the second maximum diffracted light are arranged on the horizontal axis, and the fluence F of each diffracted light at the surface of the workpiece SUB is shown on the vertical axis.

[0557] 6.1.2.1 Target fluence F OK Lower limit of mint

[0558] Similar to the modification of the second embodiment, the target fluence F OK mint is set so that the minimum value F of the first variation range of the fluence F OK min of the first minimum diffracted light OKThe mint·(1 - δE) is greater than the processing threshold Fth by such a value. Thus, the following relationship is derived.

[0559] Fth / (1 - δE) < F OK mint

[0560] The left side of the above equation, Fth / (1 - δE), is equivalent to the value obtained by adding Fth·δE / (1 - δE) to the processing threshold Fth. Fth·δE / (1 - δE) is equivalent to the first variation range in the present disclosure.

[0561] 6.1.2.2 Target fluence F OK Upper limit of mint (1)

[0562] Similar to the modification example of the second embodiment, the target fluence F OK mint is set such that the fluence F NG max of the second variation range of the second maximum diffracted light NG maxt·(1 + δE) becomes equal to or less than the processing threshold Fth. Thus, the following relationship is derived.

[0563] F OK mint ≤ (Fth / R N / O ) / (1 + δE)

[0564] The right side of the above equation, (Fth / R N / O ) / (1 + δE), is equivalent to the value obtained by dividing the processing threshold Fth by the light intensity ratio R N / O to obtain the value Fth / R N / O and then subtracting the value obtained by (Fth / R N / O )·δE / (1 + δE). (Fth / R N / O )·δE / (1 + δE) is equivalent to the second variation range in the present disclosure.

[0565] 6.1.2.3 Target fluence F OK Upper limit of mint (2)

[0566] Target fluence F OK mint is set such that the fluence F OK max of the third variation range of the first maximum diffracted light OK maxt·(1 + δE) becomes equal to or less than the fluence upper limit value Fcr. Thus, the following relationship is given.

[0567] F OK maxt·(1 + δE) ≤ Fcr

[0568] F OKmaxt is the target fluence F of the first minimum diffracted light OK multiplied by the light intensity ratio R O / O of mint. Therefore, the following relationship is derived from the above inequality.

[0569] F OK mint ≤ (Fcr / R O / O ) / (1 + δE)

[0570] As shown in the following formula, the right side of the above formula (Fcr / R O / O ) / (1 + δE) is equivalent to the value obtained by dividing the fluence upper limit value Fcr by the light intensity ratio R O / O to get the value Fcr / R O / O and subtracting the value obtained by (Fcr / R O / O ) · δE / (1 + δE).

[0571] (Fcr / R O / O ) / (1 + δE) = Fcr / R O / O - (Fcr / R O / O ) · δE / (1 + δE)

[0572] (Fcr / R O / O ) · δE / (1 + δE) corresponds to the third variation range in the present disclosure.

[0573] By setting the upper limit value of the target fluence F OK of mint like this, the maximum value F OK of the third variation range of the fluence F OK max of the first maximum diffracted light, maxt · (1 + δE), becomes a value below the fluence upper limit value Fcr. The fluences of the first diffracted light including the fluence F OK min of the first minimum diffracted light are all below the maximum value F OK of the third variation range of the fluence F OK max of the first maximum diffracted light, maxt · (1 + δE), and thus also become values below the fluence upper limit value Fcr.

[0574] 6.1.2.4 Target fluence F OK range of mint

[0575] As described above, in the modification of the third embodiment, there are two upper limits of the target fluence F OK of mint. That is, the target fluence F OK of mint is set to be below the value (Fth / R N / O ) / (1 + δE) and below the value (Fcr / R O / O ) / (1 + δE).

[0576] In the case where the ratio (Fcr / R O / O ) / (1 + δE) is larger than the ratio (Fth / R N / O ) / (1 + δE), that is, when the upper limit value of the fluence Fcr is larger than the ratio (Fth / R N / O )·R O / O , if the target fluence F OK mint is made to be below the value (Fth / R N / O ) / (1 + δE), then the value (Fcr / R O / O ) / (1 + δE) can also be disregarded.

[0577] In this case, similar to the modification example of the second embodiment, if the target fluence F OK mint is set within the range expressed by the following formula, then the fluence F OK min of the first minimum diffracted light is larger than the processing threshold Fth, the fluence F OK max of the first maximum diffracted light becomes a value equal to or less than the upper limit value of the fluence Fcr, and the fluence F NG max of the second maximum diffracted light becomes a value equal to or less than the processing threshold Fth.

[0578] Fth / (1 - δE) < F OK mint ≤ (Fth / R N / O ) / (1 + δE)

[0579] In other words, in the case where the upper limit value of the fluence Fcr is larger than the ratio (Fth / R N / O )·R O / O , the adjustment mechanism is controlled such that the minimum value F OK mint·(1 - δE) of the first variation range of the fluence F OK min of the first minimum diffracted light is larger than the processing threshold Fth, and the maximum value F NG maxt·(1 + δE) of the second variation range of the fluence F NG max of the second maximum diffracted light becomes equal to or less than the processing threshold Fth.

[0580] In the case where the ratio (Fcr / R O / O ) / (1 + δE) is smaller than the ratio (Fth / R N / O ) / (1 + δE), that is, when the upper limit value of the fluence Fcr is smaller than the ratio (Fth / R N / O )·R O / O , if the target fluence F OK mint is made to be below the value (Fcr / R O / O ) / (1 + δE), then the value (Fth / R N / O ) / (1 + δE) can also be disregarded (seeFigure 48 )。

[0581] In this case, if the target fluence F OK mint is set within the following range, the fluence F OK min of the first minimum diffracted light is greater than the processing threshold Fth, and the fluence F OK max of the first maximum diffracted light becomes a value equal to or less than the fluence upper limit value Fcr, and the fluence F NG max of the second maximum diffracted light becomes a value equal to or less than the processing threshold Fth.

[0582] Fth / (1 - δE) < F OK mint ≤ (Fcr / R O / O ) / (1 + δE)

[0583] In other words, when the fluence upper limit value Fcr is smaller than the ratio (Fth / R N / O )·R O / O the adjustment mechanism is controlled such that the minimum value F OK mint·(1 - δE) of the first variation range of the fluence F OK min of the first minimum diffracted light is greater than the processing threshold Fth, and the maximum value F OK maxt·(1 + δE) of the third variation range of the fluence F OK max of the first maximum diffracted light becomes equal to or less than the fluence upper limit value Fcr.

[0584] 6.2 Structure of the Laser Processing System

[0585] The structure of the laser processing system according to the modified example of the third embodiment is the same as that of the comparative example described with reference to Figure 1 explanation.

[0586] 6.3 Processing of the Laser Processing Processor 53

[0587] Figure 49 is a flowchart showing the processing of laser processing in the modified example of the third embodiment. Regarding the processing of laser processing in the modified example of the third embodiment, the processing of S100c and S400e is different from the corresponding processing in the third embodiment.

[0588] The details of the processing of S100c are the same as those of the modified example of the second embodiment described with reference to Figure 36 explanation. The details of the processing of S400e will be described below with reference to Figure 50 explanation.

[0589] Figure 50 is a flowchart showing the details of the processing for determining the target fluence F OK mint of the first minimum diffracted light.Figure 50 The processing shown is equivalent to Figure 49 the subroutine of the S400e.

[0590] The processing of S401b to S405d is the same as that of the third embodiment. In S405d, when the fluence F OK maxth is less than or equal to the fluence upper limit value Fcr (F OK maxth ≤ Fcr), the laser processing processor 53 causes the processing to proceed to S410c. When the fluence F OK maxth is greater than the fluence upper limit value Fcr (F OK maxth > Fcr), the laser processing processor 53 causes the processing to proceed to S412e.

[0591] In S410c, the laser processing processor 53 determines the target fluence F that satisfies the following equation, in the same manner as the modified example of the second embodiment OK mint.

[0592] Fth / (1 - δE) < F OK mint ≤ (Fth / R N / O ) / (1 + δE)

[0593] In S412e, the laser processing processor 53 determines the target fluence F that satisfies the following equation OK mint (see Figure 48 ).

[0594] Fth / (1 - δE) < F OK mint ≤ (Fcr / R O / O ) / (1 + δE)

[0595] The target fluence F OK mint can also be set to (Fcr / R O / O ) / (1 + δE) as the upper limit value. Thereby, it is possible to suppress processing of non-processing points that do not require processing and maximize the efficiency of laser processing. Alternatively, the target fluence F OK mint can also be set to the average value of Fth / (1 - δE) and (Fcr / R O / O ) / (1 + δE). Thereby, even when there is an unexpected deviation in the pulse energy of the pulsed laser Out, it is possible to avoid processing non-processing points and insufficiently processing processing points that require processing.

[0596] After S410c or S412e, the laser processing processor 53 ends the processing of this flowchart and returns to Figure 49 the processing shown.

[0597] 6.4 Function

[0598] (12) According to a modification of the third embodiment, a fluence F OK m and F NG m deviation exist between the first diffracted lights and between the second diffracted lights respectively. The laser processing processor 53 controls the adjustment mechanism to satisfy the following conditions. (a) The minimum value F OK m of the fluence F OK min of the first minimum diffracted light, the minimum value F OK mint·(1 - δE) of the first variation range based on the pulse energy deviation δE of the pulsed laser Out incident on the diffractive optical element 63 is greater than the processing threshold Fth. (b) The maximum value F NG m of the fluence F NG max of the second maximum diffracted light, the maximum value F NG maxt·(1 + δE) of the second variation range based on the pulse energy deviation δE is equal to or less than the processing threshold Fth. (c) The maximum value F OK m of the fluence F OK max of the first maximum diffracted light, the maximum value F OK maxt·(1 + δE) of the third variation range based on the pulse energy deviation δE is equal to or less than the fluence upper limit value Fcr.

[0599] Thus, not only in the case where there is a fluence deviation between multiple diffracted lights, but also in the case where the pulsed laser Out has a pulse energy deviation δE, it is possible to make the entire variation range of the fluence F OK m of the first diffracted light irradiated to multiple processing points equal to or less than the fluence upper limit value Fcr. Therefore, it is possible not only to suppress unnecessary processing and perform necessary processing, but also to suppress defective conditions such as breakage of the workpiece SUB.

[0600] (13) According to a modification of the third embodiment, the laser processing processor 53 compares the fluence F NG max of the second maximum diffracted light when it becomes the processing threshold Fth with the fluence F OK maxth of the first maximum diffracted light and the fluence upper limit value Fcr.

[0601] When the fluence upper limit value Fcr is greater than the fluence F NG max of the first maximum diffracted light when the fluence F OK max of the second maximum diffracted light becomes the processing threshold Fth, the laser processing processor 53 controls the adjustment mechanism to satisfy the following conditions. (a) The minimum value F OK min of the first minimum diffracted light, the minimum value FOK The mint·(1 - δE) is greater than the processing threshold Fth. (b) The fluence F NG max of the second variation range based on the pulse energy deviation δE, the maximum value F NG maxt·(1 + δE) is below the processing threshold Fth.

[0602] When the fluence upper limit value Fcr is smaller than the fluence F NG max of the second maximum diffracted light and becomes the processing threshold Fth, the fluence F OK maxth of the first maximum diffracted light is small, the laser processing processor 53 controls the adjustment mechanism to satisfy the following conditions. (a) The fluence F OK min of the first variation range, the minimum value F OK mint·(1 - δE) is greater than the processing threshold Fth. (c) The fluence F OK max of the third variation range based on the pulse energy deviation δE, the maximum value F OK maxt·(1 + δE) is below the fluence upper limit value Fcr.

[0603] Thus, according to the comparison result between the fluence F OK maxth of the first maximum diffracted light and the fluence upper limit value Fcr, one of the condition (b) and the condition (c) can be omitted to control the adjustment mechanism, and the control can be simplified.

[0604] (14) According to the modification example of the third embodiment, the laser processing processor 53 sets the fluence F OK min of the first minimum diffracted light, the target fluence F OK mint, and controls the adjustment mechanism such as the attenuator 52. (a) The target fluence F OK mint is greater than the value Fth / (1 - δE) obtained by adding the first variation amplitude Fth·δE / (1 - δE) representing the pulse energy deviation δE to the processing threshold Fth. (b) The target fluence F OK mint is the value obtained by subtracting the second variation amplitude (Fth / R N / O )·δE / (1 + δE) representing the pulse energy deviation δE from the value Fth / R N / O ) and is below (Fth / R N / O ) / (1 + δE), and this light intensity ratio R N / O is the light intensity I NG max of the second maximum diffracted light divided by the light intensity I OK min of the first minimum diffracted light, and this value Fth / R N / O is the processing threshold Fth divided by the light intensity ratio RN / O obtained. (c) Target fluence F OK mint is a value obtained by subtracting the third variation amplitude (Fcr / R O / O )·δE / (1 + δE) representing the pulse energy deviation δE from the value Fcr / R O / O ) / (1 + δE), and this light intensity ratio R O / O is the light intensity I O / O of the first maximum diffracted light OK divided by the light intensity I OK of the first minimum diffracted light O / O min, and this value Fcr / R O / O is obtained by dividing the fluence upper limit value Fcr by the light intensity ratio R

[0605] Thus, not only in the case where there is a fluence deviation among multiple first diffracted lights, but also in the case where there is a pulse energy deviation δE in the pulsed laser Out, when setting the target fluence F OK mint of the first minimum diffracted light, by using the light intensity ratio R O / O , it is also possible to control the fluence F OK m of the first diffracted light irradiated to multiple processing points within a desired range.

[0606] (15) According to a modification of the third embodiment, the laser processing processor 53 compares the fluence F NG max of the second maximum diffracted light with the fluence F OK maxth of the first maximum diffracted light when the fluence F

[0607] max of the second maximum diffracted light becomes the processing threshold Fth and the fluence upper limit value Fcr. NG In the case where the fluence upper limit value Fcr is larger than the fluence F OK maxth of the first maximum diffracted light when the fluence F OK max of the second maximum diffracted light becomes the processing threshold Fth, the laser processing processor 53 sets the target value of the fluence F OK min of the first minimum diffracted light, i.e., the target fluence F OK mint, and controls adjustment mechanisms such as the attenuator 52. (a) The target fluence F OK mint is larger than the value Fth / (1 - δE) obtained by adding the first variation amplitude Fth·δE / (1 - δE) representing the pulse energy deviation δE to the processing threshold Fth. (b) The target fluence F N / O mint is a value obtained by subtracting the second variation amplitude (Fth / R N / O )·δE / (1 + δE) representing the pulse energy deviation δE from the value Fth / R N / O) / (1 + δE), the value Fth / R N / O is the processing threshold Fth divided by the light intensity ratio R N / O and obtained thereby.

[0608] When the fluence upper limit value Fcr is smaller than the fluence F NG max of the second maximum diffracted light and becomes the fluence F OK maxth of the first maximum diffracted light at the processing threshold Fth, the laser processing processor 53 sets the target fluence F OK mint as follows and controls adjustment mechanisms such as the attenuator 52. (a) The target fluence F OK mint is larger than the value Fth / (1 - δE) obtained by adding the first variation amplitude Fth·δE / (1 - δE) to the processing threshold Fth. (c) The target fluence F OK mint is the value (Fcr / R O / O ) / (1 + δE) obtained by subtracting the third variation amplitude (Fcr / R O / O )·δE / (1 + δE) representing the pulse energy deviation δE from the value Fcr / R O / O and is below the value Fcr / R O / O which is the fluence upper limit value Fcr divided by the light intensity ratio R O / O and obtained thereby.

[0609] Accordingly, based on the comparison result between the fluence F OK maxth of the first maximum diffracted light and the fluence upper limit value Fcr, it is possible to set the target fluence F OK mint by omitting one of condition (b) and condition (c), and the control can be simplified.

[0610] In other respects, the modification of the third embodiment is the same as the third embodiment.

[0611] 7. Other

[0612] 7.1 Structure of the electronic device

[0613] Figure 51 Schematically shows the structure of the electronic device. Figure 51 The shown electronic device includes an integrated circuit chip IC, an interposer IP, and a circuit board CS.

[0614] The integrated circuit chip IC is, for example, a chip in which an integrated circuit (not shown) is formed on a silicon substrate. A plurality of bumps ICB electrically connected to the integrated circuit are provided on the integrated circuit chip IC.

[0615] The interposer IP has an insulating substrate in which a plurality of through-holes (not shown) are formed, and a conductor (not shown) that electrically connects the front and back surfaces of the substrate is provided in each through-hole. A plurality of connection pads (not shown) that are respectively connected to the bump ICBs are formed on one surface of the interposer IP, and each connection pad is electrically connected to any one of the conductors in the through-holes. A plurality of bump IPBs are provided on the other surface of the interposer IP, and each bump IPB is electrically connected to any one of the conductors in the through-holes.

[0616] A plurality of connection pads (not shown) that are respectively connected to the bump IPBs are formed on one surface of the circuit substrate CS. The circuit substrate CS has a plurality of terminals that are respectively electrically connected to these connection pads.

[0617] 7.2 Manufacturing method of electronic device

[0618] Figure 52 It is a flowchart showing the manufacturing method of the electronic device.

[0619] In S1, laser processing and wiring formation of the interposer substrate that constitutes the interposer IP are performed. The laser processing of the interposer substrate includes forming through-holes by irradiating the interposer substrate, which is an example of the workpiece SUB, with pulsed laser Out. The wiring formation includes forming a conductive film on the inner wall surface of the through-holes formed in the interposer substrate. The interposer IP is manufactured through such processes.

[0620] In S2, the interposer IP and the integrated circuit chip IC are combined. This process includes, for example, arranging the bump ICBs of the integrated circuit chip IC on the connection pads of the interposer IP and electrically connecting the bump ICBs and the connection pads.

[0621] In S3, the interposer IP and the circuit substrate CS are combined. This process includes, for example, arranging the bump IPBs of the interposer IP on the connection pads of the circuit substrate CS and electrically connecting the bump IPBs and the connection pads.

[0622] 7.3 Supplement

[0623] The above description is not restrictive but merely illustrative. Therefore, those skilled in the art understand that modifications can be made to the embodiments of the present disclosure without departing from the claims. In addition, those skilled in the art also understand that the embodiments of the present disclosure can be used in combination.

[0624] Unless otherwise explicitly stated, the terms used throughout this specification and the claims should be construed as "non-limiting" terms. For example, terms such as "comprising", "having", "including", and "possessing" should be construed as "not excluding the existence of structural elements other than those recited". In addition, the modifier "a" should be construed to mean "at least one" or "one or more". Further, a term such as "at least one of A, B, and C" should be construed as "A", "B", "C", "A + B", "A + C", "B + C", or "A + B + C". Moreover, it should be construed to also include combinations with parts other than "A", "B", and "C".

Claims

1. A laser processing system, comprising: A laser device that outputs pulsed laser light; A diffractive optical element that splits the pulsed laser light into light including first diffracted light and second diffracted light, where the first diffracted light is a plurality of diffracted lights respectively irradiated onto a plurality of processing points of a workpiece, and the second diffracted light is a plurality of diffracted lights irradiated onto a plurality of non-processing points; A condensing optical system that converges the first diffracted light and the second diffracted light onto the workpiece respectively; An adjustment mechanism configured to be able to adjust the pulse energy of the pulsed laser light incident on the diffractive optical element; And A processor that controls the adjustment mechanism according to a parameter including a processing threshold Fth of a fluence for processing the workpiece, so that the fluence F of the first diffracted light at the surface of the workpiece OK m is greater than the processing threshold Fth, and the fluence F of the second diffracted light at the surface of the workpiece NG m becomes equal to or less than the processing threshold Fth.

2. The laser processing system according to claim 1, wherein, The processor sets the fluence F of the first diffracted light OK to a target value, i.e., a target fluence F OK mt, and controls the adjustment mechanism so that the target fluence F OK mt is greater than the processing threshold Fth and is equal to or less than a value Fth / R obtained by dividing the processing threshold Fth by a light intensity ratio R, where the light intensity ratio R is the light intensity I NG of the second diffracted light at the surface of the workpiece divided by the light intensity I OK of the first diffracted light at the surface of the workpiece.

3. The laser processing system according to claim 1, wherein, The multiple diffracted lights of the first diffracted light and the multiple diffracted lights of the second diffracted light respectively have a deviation in fluence F OK m and F NG m, The processor controls the adjustment mechanism so that the fluence F OK of the first minimum diffracted light with the smallest fluence F OK min among the multiple diffracted lights of the first diffracted light is greater than the processing threshold Fth, and the fluence F NG of the second maximum diffracted light with the largest fluence F NG max among the multiple diffracted lights of the second diffracted light becomes below the processing threshold Fth.

4. The laser processing system according to claim 1, wherein, The multiple diffracted lights of the first diffracted light and the multiple diffracted lights of the second diffracted light respectively have a deviation in fluence F OK m and F NG m, The processor sets the fluence F among the multiple diffracted lights of the first diffracted light OK of the first minimum diffracted light with the smallest F OK min as the target value of the target fluence F OK mint, and controls the adjustment mechanism so that the target fluence F OK mint is greater than the processing threshold Fth and becomes the value Fth / R obtained by dividing the processing threshold Fth by the light intensity ratio R N / O where Fth / R N / O Hereinafter, the light intensity ratio R N / O is the light intensity I NG of the second maximum diffracted light with the largest F NG max among the multiple diffracted lights of the second diffracted light divided by the light intensity I OK of the first minimum diffracted light min.

5. The laser processing system according to claim 4, wherein, The processor calculates a parameter for adjusting the pulse energy of the pulsed laser incident on the diffractive optical element based on the ratio of the sum value Isum of the light intensities of the first diffracted light and the second diffracted light to the light intensity I OK min of the first minimum diffracted light and the target fluence F OK mint, and controls the adjustment mechanism.

6. The laser processing system according to claim 1, wherein, The multiple diffracted lights of the first diffracted light and the multiple diffracted lights of the second diffracted light respectively have a fluence F OK m and F NG m deviation The processor controls the adjustment mechanism so that the fluence F OK of the first minimum diffraction light with the smallest fluence F OK min among the multiple diffracted lights of the first diffracted light is greater than the processing threshold Fth for the minimum value of the first variation range based on the pulse energy deviation δE of the pulsed laser incident on the diffractive optical element, and the fluence F NG of the second maximum diffraction light with the largest fluence F NG max among the multiple diffracted lights of the second diffracted light becomes equal to or less than the processing threshold Fth for the maximum value of the second variation range based on the pulse energy deviation δE.

7. The laser processing system according to claim 1, wherein, The multiple diffracted lights of the first diffracted light and the multiple diffracted lights of the second diffracted light respectively have a deviation in fluence F OK m and F NG m, The processor sets the fluence F among the multiple diffracted lights of the first diffracted light OK of the first minimum diffracted light with the smallest F OK min to a target value, i.e., the target fluence F OK mint, and controls the adjustment mechanism so that the target fluence F OK mint is greater than the value obtained by adding the first variation amplitude representing the pulse energy deviation δE of the pulsed laser incident on the diffractive optical element to the processing threshold Fth and becomes less than or equal to the value obtained by subtracting the second variation amplitude representing the pulse energy deviation δE from the value Fth / R N / O , where the light intensity ratio R N / O is the light intensity I NG of the second maximum diffracted light with the largest F NG max among the multiple diffracted lights of the second diffracted light divided by the light intensity I OK min of the first minimum diffracted light, and the value Fth / R N / O is obtained by dividing the processing threshold Fth by the light intensity ratio R N / O .

8. The laser processing system according to claim 1, wherein, The multiple diffracted lights of the first diffracted light and the multiple diffracted lights of the second diffracted light respectively have a fluence F OK m and F NG m deviation, The processor controls the adjustment mechanism so that the fluence F OK m of the first minimum diffraction light with the smallest fluence among the multiple diffracted lights of the first diffracted light OK min is greater than the processing threshold Fth, and the fluence F NG m of the second maximum diffraction light with the largest fluence among the multiple diffracted lights of the second diffracted light NG max becomes below the processing threshold Fth, and the fluence F OK m of the first maximum diffraction light with the largest fluence among the multiple diffracted lights of the first diffracted light OK max becomes below the fluence upper limit value Fcr.

9. The laser processing system according to claim 1, wherein, The multiple diffracted lights of the first diffracted light and the multiple diffracted lights of the second diffracted light respectively have a deviation in fluence F OK m and F NG m, The processor calculates the fluence F among the multiple diffracted lights of the second diffracted light NG of the second maximum diffracted light with the largest fluence F NG max. When the fluence F of the first diffracted light among the multiple diffracted lights reaches the processing threshold Fth OK of the first maximum diffracted light with the largest fluence F OK maxth, it compares the fluence Fmaxth with the upper limit value Fcr of the fluence When the fluence upper limit value Fcr is greater than the fluence F NG max of the first maximum diffracted light when the processing threshold Fth is the fluence F OK maxth, Control the adjustment mechanism so that the fluence F OK of the first minimum diffraction light among the multiple diffracted lights of the first diffracted light is the minimum F OK min, which is greater than the processing threshold Fth, and the fluence F NG max of the second maximum diffraction light becomes below the processing threshold Fth. When the fluence upper limit value Fcr is smaller than the fluence F NG max of the first maximum diffracted light when the processing threshold Fth is the fluence F OK maxth of the second maximum diffracted light, Control the adjustment mechanism so that the fluence F of the first minimum diffracted light OK min is greater than the processing threshold Fth, and the fluence F of the first maximum diffracted light OK max becomes equal to or less than the fluence upper limit value Fcr.

10. The laser processing system according to claim 1, wherein, The plurality of diffracted lights of the first diffracted light and the plurality of diffracted lights of the second diffracted light respectively have a deviation in fluence F OK m and F NG m, The processor sets the fluence F among the multiple diffracted lights of the first diffracted light OK The fluence F of the first minimum diffracted light with the smallest m OK The target value of Fmin, i.e., the target fluence F OK mint, and controls the adjustment mechanism so that the target fluence F OK mint is greater than the processing threshold Fth and becomes the value obtained by dividing the processing threshold Fth by the light intensity ratio R N / O to obtain Fth / R N / O Below, and becomes the value obtained by dividing the fluence upper limit value Fcr by the light intensity ratio R O / O to obtain Fcr / R O / O Below, the light intensity ratio R N / O is the fluence F among the multiple diffracted lights of the second diffracted light NG The light intensity I of the second maximum diffracted light with the largest m NG max divided by the light intensity I of the first minimum diffracted light OK min, and the light intensity ratio R O / O is the fluence F among the multiple diffracted lights of the first diffracted light OK The light intensity I of the first maximum diffracted light with the largest m OK max divided by the light intensity I of the first minimum diffracted light OK min.

11. The laser processing system according to claim 1, wherein, The respective multiple diffracted lights of the first diffracted light and the respective multiple diffracted lights of the second diffracted light have respective fluence F OK m and F NG m deviations, The processor calculates the fluence F among the multiple diffracted lights of the second diffracted light NG of the second maximum diffracted light with the maximum fluence F NG max. When the fluence F of the first diffracted light among the multiple diffracted lights reaches the processing threshold Fth OK of the first maximum diffracted light with the maximum fluence F OK maxth, it is compared with the fluence upper limit value Fcr. When the fluence upper limit value Fcr is greater than the fluence F NG max of the first maximum diffracted light at the processing threshold Fth, OK when it is large, set the fluence F OK m of the first minimum diffracted light among the multiple diffracted lights of the first diffracted light OK The target value of min, that is, the target fluence F OK mint, and control the adjustment mechanism so that the target fluence F OK mint is greater than the processing threshold Fth and becomes the processing threshold Fth divided by the light intensity ratio R N / O to obtain the value Fth / R N / O Hereinafter, the light intensity ratio R N / O is the light intensity I NG max of the second maximum diffracted light divided by the light intensity I OK min of the first minimum diffracted light, When the fluence upper limit value Fcr is smaller than the fluence F NG max of the second largest diffracted light and the fluence F OK maxth of the first largest diffracted light is the processing threshold Fth, the target fluence F OK mint is set, and the adjustment mechanism is controlled so that the target fluence F OK mint is larger than the processing threshold Fth and becomes the value Fcr / R obtained by dividing the fluence upper limit value Fcr by the light intensity ratio R O / O Hereinafter, the light intensity ratio R O / O is obtained by dividing the light intensity I O / O max of the first largest diffracted light by the light intensity I OK min of the first smallest diffracted light. OK ​ 12. The laser processing system according to claim 1, wherein, The multiple diffracted lights of the first diffracted light and the multiple diffracted lights of the second diffracted light respectively have a deviation in fluence F OK m and F NG m, The processor controls the adjustment mechanism so that the fluence F OK m of the first minimum diffracted light with the minimum fluence among the multiple diffracted lights of the first diffracted light OK min, the minimum value of the first variation range based on the pulse energy deviation δE of the pulsed laser incident on the diffractive optical element, is greater than the processing threshold Fth, and the fluence F NG m of the second maximum diffracted light with the maximum fluence among the multiple diffracted lights of the second diffracted light NG max, the maximum value of the second variation range based on the pulse energy deviation δE, becomes equal to or less than the processing threshold Fth, and the fluence F OK m of the first maximum diffracted light with the maximum fluence among the multiple diffracted lights of the first diffracted light OK max, the maximum value of the third variation range based on the pulse energy deviation δE, becomes equal to or less than the fluence upper limit value Fcr.

13. The laser processing system according to claim 1, wherein, The respective multiple diffracted lights of the first diffracted light and the respective multiple diffracted lights of the second diffracted light have respective fluence F OK m and F NG m deviations, The processor processes the fluence F among the multiple diffracted lights of the second diffracted light NG The fluence F of the second maximum diffracted light with the largest fluence F NG max is the fluence F of the first maximum diffracted light when the processing threshold Fth OK maxth and the fluence upper limit value Fcr are compared When the fluence upper limit value Fcr is greater than the fluence F NG max of the second largest diffracted light and is the fluence F OK maxth of the first largest diffracted light at the processing threshold Fth, Control the adjustment mechanism so that the fluence F OK of the first minimum diffracted light among the multiple diffracted lights of the first diffracted light is minimized, and the minimum value of the first variation range based on the pulse energy deviation δE of the pulsed laser incident on the diffractive optical element is greater than the processing threshold Fth, and the fluence F OK of the second maximum diffracted light, and the maximum value of the second variation range based on the pulse energy deviation δE becomes equal to or less than the processing threshold Fth. NG max When the fluence upper limit value Fcr is smaller than the fluence F NG max of the first maximum diffracted light at the processing threshold Fth OK maxth, Control the adjustment mechanism so that the minimum value of the first variation range of the fluence F of the first minimum diffracted light is greater than the processing threshold Fth, and the maximum value of the third variation range based on the pulse energy deviation δE of the fluence F of the first maximum diffracted light is equal to or less than the fluence upper limit value Fcr. OK OK ​​ 14. The laser processing system according to claim 1, wherein, The multiple diffracted lights of the first diffracted light and the multiple diffracted lights of the second diffracted light respectively have a deviation in fluence F OK m and F NG m, The processor sets the fluence F among the multiple diffracted lights of the first diffracted light OK of the first minimum diffracted light with the smallest F OK min to a target value, i.e., the target fluence F OK mint, and controls the adjustment mechanism so that the target fluence F OK mint is greater than the value obtained by adding the first variation amplitude representing the pulse energy deviation δE of the pulsed laser incident on the diffractive optical element to the processing threshold Fth, and becomes a value from Fth / R N / O subtracting the second variation amplitude representing the pulse energy deviation δE and is less than or equal to the value obtained by subtracting the third variation amplitude representing the pulse energy deviation δE from the value Fcr / R O / O subtracting the third variation amplitude representing the pulse energy deviation δE, and the light intensity ratio R N / O is the fluence F among the multiple diffracted lights of the second diffracted light NG of the second maximum diffracted light with the largest I NG max divided by the light intensity I of the first minimum diffracted light OK min, and the light intensity ratio R O / O is the fluence F among the multiple diffracted lights of the first diffracted light OK of the first maximum diffracted light with the largest I OK max divided by the light intensity I of the first minimum diffracted light OK min, and the value Fth / R N / O is the processing threshold Fth divided by the light intensity ratio R N / O and the value Fcr / R O / O is the upper limit value of fluence Fcr divided by the light intensity ratio R O / O and is obtained in this way.

15. The laser processing system according to claim 1, wherein, The plurality of diffracted lights of the first diffracted light and the plurality of diffracted lights of the second diffracted light respectively have a fluence deviation of F OK m and F NG m, The processor processes the fluence F among the multiple diffracted lights of the second diffracted light NG The fluence F of the second maximum diffracted light with the largest fluence F NG max. When the fluence F among the multiple diffracted lights of the first diffracted light is the processing threshold Fth OK The fluence F of the first maximum diffracted light with the largest fluence F OK maxth is compared with the fluence upper limit value Fcr When the fluence upper limit value Fcr is larger than the fluence F NG max of the second largest diffracted light and is the fluence F OK maxth of the first largest diffracted light at the processing threshold Fth, set the fluence F OK m of the plurality of diffracted lights of the first diffracted light to be the minimum, i.e., the fluence F OK min of the first minimum diffracted light as the target value, i.e., the target fluence F OK mint, and control the adjustment mechanism so that the target fluence F OK mint is larger than the value obtained by adding the first variation amplitude indicating the pulse energy deviation δE of the pulsed laser incident on the diffractive optical element to the processing threshold Fth and becomes a value from Fth / R N / O subtracting the second variation amplitude indicating the pulse energy deviation δE and is below the value, the light intensity ratio R N / O is the light intensity I NG max of the second largest diffracted light divided by the light intensity I OK min of the first minimum diffracted light, and the value Fth / R N / O is the processing threshold Fth divided by the light intensity ratio R N / O and is obtained thereby. When the fluence upper limit value Fcr is smaller than the fluence F NG max of the second maximum diffracted light and the processing threshold Fth is the fluence F OK maxth of the first maximum diffracted light, the target fluence F OK mint is set, and the adjustment mechanism is controlled so that the target fluence F OK mint is larger than the value obtained by adding the first variation range to the processing threshold Fth and becomes a value obtained by subtracting the third variation range representing the pulse energy deviation δE from the value Fcr / R O / O . The light intensity ratio R O / O is the light intensity I OK max of the first maximum diffracted light divided by the light intensity I OK min of the first minimum diffracted light. The value Fcr / R O / O is the fluence upper limit value Fcr divided by the light intensity ratio R O / O .

16. A laser processing method, comprising the following steps: Output pulsed laser light from a laser device, Split the pulsed laser light into light including first diffracted light and second diffracted light through a diffractive optical element, where the first diffracted light is a plurality of diffracted lights respectively irradiated onto a plurality of processing points of a workpiece, and the second diffracted light is a plurality of diffracted lights irradiated onto a plurality of non-processing points, Controlling an adjustment mechanism that adjusts the pulse energy of the pulsed laser according to a parameter including a processing threshold Fth of a fluence for processing the workpiece, such that the fluence F OK m of the first diffracted light at the surface of the workpiece is greater than the processing threshold Fth and the fluence F NG m of the second diffracted light at the surface of the workpiece becomes equal to or less than the processing threshold Fth Converge the first diffracted light and the second diffracted light onto the workpiece respectively through a condensing optical system.

17. The laser processing method according to claim 16, wherein, Measure the light intensity I of the first diffracted light at the surface of the workpiece to be machined OK and the light intensity I of the second diffracted light at the surface of the workpiece to be machined NG , Set the fluence F of the first diffracted light OK The target value of m, i.e., the target fluence F OK mt, and control the adjustment mechanism so that the target fluence F OK mt is greater than the processing threshold Fth and becomes a value equal to or less than the processing threshold Fth divided by the light intensity ratio R, where the light intensity ratio R is the light intensity I NG of the second diffracted light divided by the light intensity I OK of the first diffracted light.

18. The laser processing method according to claim 16, wherein, Measure the fluence F among the multiple diffracted lights of the first diffracted light OK The light intensity I of the first minimum diffracted light with the smallest m OK min and the fluence F among the multiple diffracted lights of the second diffracted light NG The light intensity I of the second maximum diffracted light with the largest m NG max, Set the fluence F of the first minimum diffracted light OK of the target value, i.e., the target fluence F OK mint, and control the adjustment mechanism so that the target fluence F OK mint is greater than the processing threshold Fth and becomes the processing threshold Fth divided by the light intensity ratio R N / O to obtain the value Fth / R N / O Hereinafter, the light intensity ratio R N / O is the light intensity I NG max of the second maximum diffracted light divided by the light intensity I OK min of the first minimum diffracted light and obtained thereby.

19. The laser processing method according to claim 16, wherein, Measure the fluence F among the multiple diffracted lights of the first diffracted light OK The light intensity I of the first minimum diffracted light with the smallest m OK min, the fluence F among the multiple diffracted lights of the second diffracted light NG The light intensity I of the second maximum diffracted light with the largest m NG max and the fluence F among the multiple diffracted lights of the first diffracted light OK The light intensity I of the first maximum diffracted light with the largest m OK max, Set the fluence F of the first minimum diffracted light OK The target value of min, i.e., the target fluence F OK mint, and control the adjustment mechanism so that the target fluence F OK mint is greater than the processing threshold Fth and becomes the value obtained by dividing the processing threshold Fth by the light intensity ratio R N / O Fth / R N / O Below, and becomes the value obtained by dividing the fluence upper limit value Fcr by the light intensity ratio R O / O Fcr / R O / O Below, the light intensity ratio R N / O Is the light intensity I of the second maximum diffracted light NG max divided by the light intensity I of the first minimum diffracted light OK min, and the light intensity ratio R O / O Is the light intensity I of the first maximum diffracted light OK max divided by the light intensity I of the first minimum diffracted light OK min.

20. A method for manufacturing an electronic device, comprising the following steps: Perform laser processing on an interposer substrate through a laser processing system to fabricate an interposer, Bond the interposer and an integrated circuit chip to electrically connect them to each other, Bond the interposer and a circuit board to electrically connect them to each other, The laser processing system comprises: A laser device that outputs pulsed laser light; A diffractive optical element that splits the pulsed laser light into light including first diffracted light and second diffracted light, where the first diffracted light is a plurality of diffracted lights respectively irradiated onto a plurality of processing points of a workpiece, and the second diffracted light is a plurality of diffracted lights irradiated onto a plurality of non-processing points; A condensing optical system that converges the first diffracted light and the second diffracted light onto the workpiece respectively; An adjustment mechanism configured to be able to adjust the pulse energy of the pulsed laser incident on the diffractive optical element; and A processor that controls the adjustment mechanism according to a parameter including a processing threshold Fth of a fluence for processing the workpiece, so that the fluence F of the first diffracted light at the surface of the workpiece is greater than the processing threshold Fth, and the fluence F of the second diffracted light at the surface of the workpiece becomes equal to or less than the processing threshold Fth. OK m is greater than the processing threshold Fth, and the fluence F of the second diffracted light at the surface of the workpiece NG m becomes equal to or less than the processing threshold Fth.

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